The Discus

The Discus is known as the "King of the Aquarium". Perhaps the most beautiful of all tropical fish, the Discus is also one of the more difficult tropical fish to keep and is not recommended for beginners.
They require excellent water conditions, frequent water changes and higher water temperatures than most other tropical fish. Most successful keepers house them in a species only tank because of the high water temperature requirement. There are many color varieties to choose from with many more being introduced all the time. If you are interested in this fish, be prepared to spend some jack on this one of a kind tropical fish.

The Yellow-head Jawfish

The Yellow-head Jawfish is a wonderful looking fish with a bright yellow head and a white or light blue body. They like to burrow in the substrate and prefer a deeper sand bed with crushed coral and various grades of sand, at least 3 to 5 inches. They have the incredible ability to quickly dart back into their burrow tail first when spooked. You usually won't see them swimming around alot. They like to hang vertically above the burrow or in the burrow with only their yellow heads poking out. It's really neat to see a colony of them in a tank hanging vertically above their holes watching you. They should do well with other peaceful marine fish and you should be able to keep multiple yellow jawheads in the same tank, provided that there is enough territory for each. However, the different jawfish species may not co-exist peacefully in the same tank. They have been known to jump out of tanks when first introduced, so you'll need a good tight fitting hood with no possible escape points.
The Yellow-head Jawfish is primarily a carnivore and need meaty foods in their diet. At first, you may need to deposit the food near the burrow opening to entice them to eat. After they become acclimated they may become less shy and may come out of the burrow to eat. Be warned, they may nip at and eat small crustaceans.
They seem to be fairly disease resistant but you still need to take proper pre-cautions and use a quarantine tank before introducing them into your main tank.
 

Dwarf Gourami

More Common Names: Blue Dwarf Gourami, Sunset Gourami, Powder Blue Gourami, Neon Dwarf Gouramis

Originating in the waters of India, the Dwarf Gourami is not only beautiful but they can be particularly hardy as well. The male is more colorful while the females are less colorful. Usually the female Dwarf Gourami is gray in appearance. There are a couple of color varieties including the Blue and the Flame Red.
They make a great addition to a fully cycled community tank and are easy to care for. They should accept most fish food including flakes, freeze-dried, frozen and live foods.
If you notice the coloration on your dwarf gouramis starting to fade, try supplementing their diet with freeze dried blood worms or live foods once in a while. They are not picky eaters.

Be a Responsible Fish Keeper

If you spend any amount of time browsing the fish forums you will soon come to the realization that there are many pet fish keepers that are totally unprepared and not very responsible when it comes to keeping aquariums. It’s unfortunate that fish are not afforded the same level of care as other pets such as dogs or cats.
Many people think less of fish for some reason. Maybe because fish is a part of our diet? I don’t understand why they don’t care more deeply for the animals they are keeping. So, what does it mean to be a “responsible fish keeper”?
To me, being a responsible aquarist means:

• Taking the time to research all the fish and invertebrates you’re interested in keeping before buying them.
• Not keeping fish in bowls or other small containers with no methods of filtration or temperature control.
• Not buying a small tank for a child and assuming that they will be the primary care giver of the fish and aquarium. Although I think keeping fish can be a wonderful learning experience for children and I think it can help instill responsibility in them, realize that you (the parent) will be the primary care person for this tank. Children lose interest quickly and while they may be very interested at first, they will often forget about the tank after awhile.
• Understanding that this is a long-term hobby. Many species can live for a very long time. For instance, Goldfish can live for many years (10 or more years) if kept in optimal conditions.
• Keeping fish in adequately sized tanks. How many posts have you read about hobbyists keeping a common pleco in a 10 gallon tank?
• Not overcrowding! I understand the temptation to get “just one more fish” and I have to fight it myself. But understand that it is better for your aquarium’s inhabitants and better for you in the form of less maintenance. Less fish in your tank equates to less bio-load, which means less dissolved organics which means less water changes. Speaking of water changes….
• Performing regular partial water changes. Probably the best thing we can do to keep our systems stable is to perform small and frequent partial water changes. You want to use decholorinated water (either tap or reverse osmosis water) that has been adjusted temperature wise to your tank water. This is especially important in overstocked tanks or aquariums with no mechanisms for nitrate reduction.
• Don’t believe the rule that fish will regulate their growth depending on the size of the tank they’re kept in. They may grow more slowly, but it is not directly caused by the fish tank size. It is cause by the amount of dissolved organics and other pollutants that quickly accumulate from the bio-load in the tank. Fish that are kept in optimal conditions will continue to grow to their adult size in favorable aquarium conditions.
• Knowing about the aquarium nitrogen cycle. Although it may take a tiny bit of effort understanding this cycle, this is really basic stuff here. This would also mean not subjecting fish to the rigors of cycling a tank. Some species such as zebra danios are hardy, but they still suffer when subjected to ammonia and nitrites in the first stages of a cycle. There are many products available containing the bacteria needed to speed this cycle up and their is no reason anymore to subject fish to this.
• Using a quarantine tank for several weeks to monitor your new fish before introducing them to your main aquarium. This gives them time to adjust and you can improve their health by feeding them high quality foods before introducing them to the competitive environment in the display tank. Fish disease may show up in the first days or weeks and having them in quarantine prevents the spread of this disease to the other fish and you can easily treat them in the qt tank. It is also more economical to treat them in a smaller volume of water.
• Knowing what you’re buying. This holds especially true for saltwater reef tank keepers. Many corals can be easily fragged and aquacultured. Some species of fish, such as the neon goby and clownfish can be aquacultured as well. We need to encourage this activity and support those dealers that sell aquacultured species.

It’s really not difficult to be a better, more responsible fish keeper. It just takes a little work on your part to take the time to read and research your animals and understand some basic aquarium concepts. It also good for your karma.

Are you over medicating your fish?

The idea behind this post comes after reading several boards on various fish and aquarium forums across the great wide web. I’m always coming across posts that start off like this: “I recently set up a new tank and now I think all the fish have ich”. Or, “My fish has fin rot what can I do?”. Then you see all the responses from the others on such and such medicine and such and such treatment. Why do we think medications will fix our shortcomings as aquarists?Let me start this off by stating that while I’m all in favor of using medicines and other treatments in the right situation, I really do feel that most of them are misused and they are used much too often to treat our aquarium fish.
Take fin rot for example. Fin rot can usually be “cured” by simply providing a good diet, clean, frequently changed aquarium water and any fin nipping tank mates. No medicines are necessary. Bada-bing, poof - fin rot gone.
Ich is another easily preventable disease, but one that will benefit from using medicine to fight this fish disease in a quarantine tank before introducing it to your main tank and infecting ALL the fish in the aquarium. Developing a proper quarantine protocol with ALL new fish is an absolute. The aquarist can watch for any signs of infection and/or disease and treat if necessary in the quarantine tank. It’s too bad since this disease is so easily prevented and often fatal for our fish.
Ok, by a show of hands please, how many of you use a quarantine tank? Not many I see. It’s too bad, because you really could make it easier on yourself and your wallet by using one for you new fish friends. One of the best things you can do for your fish, aside from using a quarantine tank, is to do those partial water changes on a regular basis. Our aquariums are enclosed systems and they can quickly become polluted. Frequent partial water changes dilutes the levels of pollution in our tanks and can keep the fish from stressing. Once stressed, their immune systems may be lowered making it easier for them to contract a disease, fungus or other problem.
So, if you discover a problem with your fish such as fin rot or a fungus remember back to when your last water change was… Has it been awhile? Try getting and keeping the water cleaner before resorting to using medications.
Sorry for the rant, but I get tired reading about how much money gets wasted on all these fish medicines!

Aquarium Test Kits

A very important part of keeping fish in aquariums is testing the water periodically. There are many different types of aquarium test kits out there and it can be confusing in deciding which ones to get and what to test for in your fish tank.

If you have a newly setup fish tank, you will want to get and test for at least the following:
Test Kits For Freshwater Aquariums:

• Ammonia - the first stage of the nitrogen cycle, this will kill your fish if they are exposed long enough to it. You need to test for ammonia and if you get even a low reading on the test kit, partial water changes are required.
• Nitrite - will show up in the second stage of the nitrogen cycle. This too will kill your fish if they are in it long enough. Again, partial water changes are required.
• Nitrate- the third stage of the aquarium cycle is nitrate. While not as damaging as ammonia or nitrite, nitrate at high enough levels is not good for your tank’s inhabitants. To get rid of nitrates you can do water changes, get a denitrator (expensive) or use more live plants in freshwater tanks.
• pH- is needed to determine which types of fish will go well with your water without using any commercial additives and to periodically check to make sure nothing is too out of whack with the system. Accumulating organics tend to drive pH down, indicating that you may be overdue for a partial water change.

Test Kits For Saltwater Aquariums:

• Ammonia - see above.
• Nitrite - see above.
• Nitrate- use more live rock and deep sand beds in saltwater tanks, grow macro algae in a refugium or sump.
• Calcium- you will need to test for calcium if you want to grow the purple and pink coralline algae (may need lower lighting levels too) and if you want to keep calcium needing organisms such as clams and corals.
• Phosphate- can be a limiting factor in algae blooms/growth. Keeping phosphates near zero can be hard to do because it is introduced into the tank in many ways such as through foods and top-off water. If you have problems with phosphates, consider using Reverse Osmosis water and feed the fish very small quantities at a time. Test your activated carbon for phosphates too before using it.
• Alkalinity- can be a very important thing to test for to make sure that the buffering capacity is in an acceptable range, which is 2 - 2.6 meq/L.
• Iodine- a pet peeve of mine is to hear about folks dosing iodine without testing first. How can you possibly know if you’re dosing too much or even if you need to dose it at all without a test kit?
• Silicate - the accuracy of these test kits have been questioned and it is not all that necessary, although it can be a factor in algae growth (diatoms).
• pH - needed to make sure that the pH is staying within an acceptable range. I would really recommend getting one of the digital pH meters. Test your aquarium in the middle of the day and then again first thing in the morning. Chart your readings to get a good understanding of the system fluctuations. Too much of a swing could indicate something that needs fixing.
• Dissolved Oxygen- is a test kit that is not really needed in my opinion unless you’re walking a fine line with an overstocked aquarium. If you have adequate surface agitation and you use a properly sized protein skimmer on your tank, dissolved oxygen levels should be fine.
• Hydrometer - The hydrometer will measure specific gravity and it should be in a range of 1.021 - 1.025.

1 Inch of Fish Per Gallon of Water Rule

The 1 inch of fish per liter of water control


As a frequent browser several fish and aquarium forums, I often come on a lot of things about me go "make Huh?". You'll also see this one inch of fish per liter) of water rule (or guideline to some of the fish and aquarium-represented sites in the network. Let's talk about why this rule does not hold water.

Size Matters (fish)

While this rule for some of the smaller species of fish available to us to work, it does not work for the majority. You see, growing fish. Most of the fish that we are receiving, held by the local fish and when we have young people through its current size when purchasing if you are the rule, we are definitely problems as they grow.

If your bearing 10 liter tank with ten, 1 inch Oscars, you will soon need either a Rogaine, Excedrin, a new tank or all of the above. Oscars may be, for example, grows to over 12 inches as adults! So if you have a constant flow of fresh water aquarium, give this 10 gallon tank and under the assumption that they were not together (NOT!) And assume that they would fight to live to maturity, you may have 120 inches of fish in your 10 liter tank. Just a bit crowded.

I could see where you could use this rule to say, 5 - two-inch neon tetras in a 10 liter tank. This would be my opinion, still overcrowded, even if water to ensure optimal conditions. It is definitely not as bad as the Oscar-scenario. Look at the size of adult fish potential purchases before buying, to see if they go well in your aquarium.

View Aquarium Shape

We must also remember that large fish need more oxygen dissolved in the water than smaller fish. Big fish also produce large quantities of waste. Leave us a 10 liter tank, for example again. A 10-inch Oscar produce significantly more waste than 10, 1 inch neon tetras. During the same 10-inch Oscar too much dissolved oxygen as the need tetras. If you shaped molded a 10 gallon rectangular tank, it would be better than a 10 gallon tank large hexagon. The rectangular tank is taking place to ensure a larger surface area for gas exchange. Carbon dioxide is passed, the water and oxygen enter the water at the surface of the tank. That is why you are here, sometimes people favor more surface agitation in heavily stocked tanks. This surface agitation allowing gas exchange.

Fish Temperament is also important to

If you are on your 10 gallon aquarium with 3 Neon Tetras stock (approx. 6 cm for adults) and 1 Convict cichlid (about 4 cm as an adult) they recommended was in the 10 inches by this silly rule, and you can believe it is to go in order and to receive this combination. Well, how many Convict cichlid keeper would you say these 3 Neon Tetras probably not long for that setup last. If they have not eaten, they can be harassed to death by these cichlid fighting. Although holding only one in this tank, it can limit aggression, I would be willing to bet that the neons would not last a month in this tank.

These were just some of the things I thought I'd throw it to those who use this rule to have their tanks in stock. I hope you can say that it does not take the best rule, and that it really works only for the small fish species that stay small. But even then, why make more work for yourself exhausted with water changes in your tank? Stock on the bright side and make less work for you. Your fish can behave very differently even more space and less competition for aquarium food.

SEA WATER

The main difference between fresh water and sea water is that the latter contains a great
many salts which give it certain specific characteristics, and these must be understood by
any aquarist who wishes to keep marine fish.

TEMPERATURE
The temperature of tropical sea water
varies little over the course of a day, or
even a year. Furthermore, marine fish are
generally more sensitive to abrupt
changes than freshwater fish. The temperature
in an aquarium must, therefore, be
fairly stable, remaining at around 25-26°C.

SALINITY
The most important salt found in sea
water is sodium chloride (NaCl), widely
used for domestic and culinary purposes,
but there are plenty more.
The salinity of water, i.e. the quantity of
salts in the water, is expressed in 0/00 or in
g/liter. The mean salinity of the Earth's
oceans is around 350/00, or approximately
35 g salts/liter.
Whatever its salinity, sea water boasts one
remarkable property: the proportion of
each element is constant.
Desalinated water does not therefore contain
less of one or more salts, but the
combination of salts is present in a lower
concentration.
The salinity of sea water varies according
to longitude. It is at its highest in open
seas in the tropics, it is lower near coasts
and after heavy rain, and it is at its lowest
near the poles (due to the influence of
melting snow).
 
DENSITY
In marine aquariums, it is not the salinity
of water which is measured, but the density
(often expressed as specific gravity,
S.G.), which can be calculated according
to the following formula:

you need to know about loaches ?

The first loach I am going to talk about is the clown loach (Chromobotia macracanthus). These like to be kept in groups peferably 4+. These are sold small and rarely ever bigger then 3″. Once they hit the 4″ they grow very slow, 1″ to 1″ and half a year. I would recommended them growing out in nothing smaller then a 75 and need to be a 125-150 when full grown.  They grow to somewhere around 14-16 inches long and when mature the females get more plump. As like most loaches they are snail eaters. They like blood worms and insect larvae.  A more smaller species is the yo-yo loach (Pakistani). These are ideal snail eaters and will eat everyone in your tank. They also do good in groups 5+. They are planted tank friendly and are very nice fish. The top out at around 6 inches and pretty peaceful. They don’t get along with shrimp and will eat them (watched first hand). They like well oxygenated water and don’t mind currents.  This is one of my favorite loaches, and Its called the Horseface loach (Acantopsis choirorhynchos). I have kept these in groups 3 to 5. They can be territorial so i recommend 1 loach per 35 gallons and add another 10 gallon for each additional loach. They need to be kept in sand, they like to hide and play in it. They also need lots of hiding spaces and need to fed at night. They enjoy any type of live foods, and might have to ween off of them. I feed my NLS, live and frozen brine shrimp. They prefer lower PH (6.0-7.2).  The smallest of the loaches is the Dwarf Loach (Yasuhikotakia sidthimunki). No reason should they be kept in groups under 7 loaches. They are one of the most social fish and need the groups. They are a bit pricey so i would save up before buying them. They like to be kept in lower ph (6.0 range) and  could be kept as high as 7.5.  Kuhli loachs (Pangio kuhlii) is a nice little fish. they need hiding spaces and like groups of 4+. They should not be kept in anything smaller then a 45, do to the activeness at night. They accept wide variety of food and range of water quality. There are

What Freshwater Aquarium Fish Can I keep Together?

Many people ask us a lot of questions about:  what fish can I keep in my tank so no body will fight with each other? The answer is simple, there are many of compatible fish and today we’ll try to answer this question. If you have freshwater aquarium fish than we’ll give you a list of fish that can and can’t be kept in one tank,ok?  So lets start from cichlids and one of them is none agressive – Angelfish. Ok so lets see you have Angels, if you didn’t know they also belong to cichlid family, BUT they are not aggressive as their relatives. Angels can be easily kept with community fish like guppies, mollies, red sword tails, glownfish, catfish, cory fish, etc. Angelfish are peaceful and won’t make any problems for you unless you’ll have guppy or moly fry, than they’ll think that it’s food and they will definitely eat them.  Now let’s go to agressors. Under this goes African cichlids that are semi aggressive and more aggressive fish like Oscars, Jack Dampsey, etc. All of them must be kept away from community fish like we showed before and from others that aren’t that aggressive.  If you’ll have something like medium guppy and medium African cichlid in one tank than African one will start nipping your guppy and we’re sure you don’t want to see something like that. Please avoid that. Cichlids with cichlids, community fish with community fish.  If you have BETA fish in bigger tank than just bowl, than you’ll be able to have also red sword tails, black/silver mollies, angels, cat fish, cory fish, and other friendly fish. Please avoid all kinds of barbs because they’ll nip your beta and other fancy (with long fins) fish.  Goldfish can be also kept with community fish that we indicated above.  We hope it was useful for you to read this article and If you have any questions about aquarium fish keeping

Betta Basic Care Sheet

Betta Splendens (pronounced BET-uh)  Temperature: 75 to 82 degrees  Housing: . A heated 2.5 gallon tank is recommended for a single betta, though the bigger the better. Because they originate from the slow moving water of rice paddies, a strong current, either from a filter or a bubbler will blow their long fins around and cause them unnecessary stress. As they take oxygen directly from the air, the width of the container is more important to the fish than height. Your fish will also appreciate at least a couple of hiding spots, such as caves, rocks, and other décor, and hardy live plants such as java fern, which also look great in a tank setup. Depending on the size of the tank, water changes will have to be done weekly. For a 2.5 gallon, 100 percent of the water should be changed weekly. In a bigger tank, such as a cycled 5 or 10 gallon, 20 percent water changes can be done weekly.  Diet: Bettas are carnivores, and should be fed mainly on a pellet diet, which can be supplemented by a variety of other foods, such as live/frozen/freeze-dried brine shrimp, daphnia, blood worms, as well as live fruit flies, and fruit fly larvae.  Tankmates: Bettas should NEVER be kept together, as they are highly territorial and will fight each other. However, they can be kept with other peaceful species, like cory cats, ottos, white cloud minnows, and African dwarf frogs. They should not be kept with large or aggressive fish such as cichlids, angels, and danios, or coldwater fish, like goldfish.  Lol, thats my first attempt at writing a caresheet, and if you see something wrong or want to add something, please let me know!  Article written by Bettaholic

Common Goldfish

Scientific Name Carassius auratus
Natural Habitat The Goldfish was bred from Crucian Carp in China during the time of the Tang Dynasty
Size 13 inches is an average maximum size although Goldfish have been known to grow to lengths as long as 23 inches

Temperment Peaceful, will eat fish small enough to fit in their mouth
Aquarium 125 litres
Comments The Goldfish was the first fish to be kept as a pet. It was bred from the Crucian carp over a thousand years ago in China and even today remains one of the most popular species in the hobby. Popular belief that the Goldfish is a small species that will live happily in a bowl couldn’t be further from the truth. The Goldfish is a hardy fish yet like all species poor conditions will cause it stress and eventually death.
These large fish should be kept in aquariums that suit its large size. An aquarium holding 125 litres is the minimum for three Goldfish although the bigger the aquarium the better. As you probably know already temperature is not a concern when keeping Goldfish so a heater is not neccessary. Many people keep Goldfish in garden ponds and if you ask me this is the best place for them unless you can supply them with a very large aquarium. You should also include an air pump for Goldfish as a lack of oxygen in the water will also cause them stress. Lastly and perhaps most importantly is providing a good filter.
Goldfish produce far more waste then other species of fish so correct filteration is a must. Weekly water changes of 25% to 40% are also needed to remove any waste from the aquarium and keep the water in good quality. There are not many species which can be kept with Goldfish. If you have a very large aquarium then it is possible to keep them with Weather Loach. I would not recommend keeping Common Goldfish with Fancy Goldfish however. Common Goldfish are far faster then the Fancy Goldfish due to there more streamline shape. Common Goldfish will thus eat any food you put into the aquarium before the Fancy Goldfish have a chance. Common Goldfish will also occasionly mistake Fancy Goldfish for being pregnant and take the oppertunity to chase and bully them. Feeding the Common Goldfish isn’t a hard, most fish stores should have a selection of granule and flake food which are purpose produced for the nutritional feeds of Goldfish. Feed Goldfish a small amount of food once a day and remove any food which is not consumed in 4 minutes.
If you have any questions, feel free to ask on our forum.

Fancy Goldfish

Scientific Name Carassius auratus  Natural Habitat Fancies are not found in the wild. They are the result of selective breeding of the Common Goldfish which in turn was bred from the Crucian Carp around 1,000 years ago  Size Around 6 inches in aquariums although they are reports of Fancies growing to 18 inches in length  Temperment Peaceful with each other, will eat small subtropical fish  Aquarium 60 litres at least but the more the better  Comments Where would we be today without the odd Goldfish or two? The Fancies relative, the common goldfish, were the first fish to be kept around 1,000 years ago in China. Unlike today they were a sign of wealth and royalty, especially yellow strains such as the popular yellow canary Goldfish. So much so that it was illegal in China for anyone other then the Emperor to own the Yellow Goldfish.  Fancy Goldfish are far removed from these fish kept in ancient China however. Years of selective breeding have given the hobby many different shaped and colored Fancies. There are many strains of Fancies available such as the popular Oranda (above,) the Ranchu, Lionhead and Fantail. Most strains of Fancy Goldfish are considered to be rather resilient and the perfect fish for beginners. This is however not the whole case as Fancies grow very large and produce a lot of waste and so require weekly partial water changes and a good filtration system. If this can be provided then they are a wonderful fish to own but it should also be added that some species are not as resilient as others such as the Pearlscale Goldfish. It should also be mentioned that although many Fancies are resilient, they will not stand the cold temperatures of the garden pond as Common Goldfish can. This is due to generations of these fish being bred indoors.  Swimbladder disorder is also common in Fancies but this is easily corrected. Because Fancies have been bred to have a round body, this extra body mass puts a strain on the Fancie’s swimbladder and can result in any air becoming trapped in the fishes swimbladder

Fish catagories

There are more than 30,000 species of fish, more or less evenly distributed between fresh water and sea water, and of these some 1,500 are of interest to the aquarist. Fish embody a great anatomical and biological diversity and richness, and this can be clearly seen in aquariums.
Whatever type of aquarium you choose, a minimal knowledge of the anatomy and biology of the species you are raising is an essential prerequisite. The information below, presented in layman's language, allows you to keep your fish in good health, in the best possible conditions, to feed them appropriately so that they can grow, and to facilitate their reproduction — in short, to understand them better in order to take better care of them.

FINDING OUT THE CHARACTERISTICS OF NATURAL WATER

The European Union has set compulsory standards for drinking and environmental quality, but the strict legislation in the UK goes well beyond these. In England and Wales, for example, domestic water is monitored by the Drinking Water Inspectorate, which regularly checks up on the practices of the water companies and investigates any possible infringement of the law. The Environment Agency, on the other hand, is responsible for the quality of water in rivers, estuaries, and coastal areas. It issues licenses to discharge waste into these waters and takes chemical and biological samples to monitor the effect on the environment. The results of these controls are available to the public.

Where and when to collect natural sea water?

The ideal solution would be to go to the open sea, where the water is likely to be less polluted and to have more constant characteristics. Near the coasts, the following must be avoided: urbanized or industrialized areas and ports, which are susceptible to pollution; anywhere near river mouths, estuaries, or bays, where the water is desalted; and areas of stagnant sea water (pools at low tide) and salt marshes. Coasts with sand dunes are suitable in principle, but the water is often laden with suspended sediment. Rocky coasts are preferable regions from where water can be collected. The best periods for collection are autumn and winter, because plankton develop in spring and tourism increases the risk of pollution in summer. Calm weather is preferable, in order to avoid suspended material, although a heavy swell re oxygenates the water. In this case, the water can be collected 1-3 days later, the time in which the suspended material turns into sediment. However, the water must be filtered in all cases, first roughly and then more finely.

WATER, A HAVEN FOR LIFE

water, carbonate hardness (CH) is used in sea water, where it serves to measure the
quantity of calcium and magnesium carbonates and bicarbonates present. This is crucial for maintaining the pH, and for growing corals, which have skeletons made of calcium carbonate.

PH VALUES
As sea water is salty, its pH is therefore higher than that of fresh water. Pure sea
water in the middle of the ocean has a pH of 8.3- Near the coasts, this drops to about
8 or a little less, as its dilution with fresh water lowers the salt content. The pH of
sea water in an aquarium must vary between 8 and 8.5; beyond these values,
animals will experience certain physiological problems.
Variations in pH in a marine aquarium Sea water contains a great deal of calcium carbonate
and bicarbonate, and there are only slight variations in pH in a natural setting.
It is a different matter in an aquarium, a restricted habitat operating as a closed
cycle. The pH must not fall below 8, but a slow and regular decrease in this parameter
may be seen. Why? The water in an aquarium sometimes contains too much
carbon dioxide, which has a tendency to lower the pH.
What can you do? The first step is to measure the CH:  if it is under 7.2°CH, add calcium or
replace some of the water. This situation is, however, fairly rare in an aquarium without
corals, solely occupied by fish; if it is over 7.2°CH, there is an excess of
carbon dioxide. Stirring of the water must therefore be increased by using diffusers or
an electric pump.

THE NITROGEN CYCLE
This occurs in the same way in sea water and fresh water. In a marine aquarium the
vegetation is often less abundant than in fresh water, and so the nitrates, the end
products of the nitrogen cycle, will have a tendency to accumulate.
At high doses these pose little danger to fish but are toxic for invertebrates, especially
corals. It is therefore important to eliminate them by partial, but regular,
water changes.

SEA WATER

The main difference between fresh water and sea water is that the latter contains a great many salts which give it certain specific characteristics, and these must be understood by any aquarist who wishes to keep marine fish.

TEMPERATURE
The temperature of tropical sea water
varies little over the course of a day, or
even a year. Furthermore, marine fish are
generally more sensitive to abrupt
changes than freshwater fish. The temperature
in an aquarium must, therefore, be
fairly stable, remaining at around 25-26°C.

SALINITY
The most important salt found in sea
water is sodium chloride (NaCl), widely
used for domestic and culinary purposes,
but there are plenty more.
The salinity of water, i.e. the quantity of
salts in the water, is expressed in 0/00 or in
g/liter. The mean salinity of the Earth's
oceans is around 350/00, or approximately
35 g salts/liter.
Whatever its salinity, sea water boasts one
remarkable property: the proportion of
each element is constant.
Desalinated water does not therefore contain
less of one or more salts, but the
combination of salts is present in a lower
concentration.
The salinity of sea water varies according
to longitude. It is at its highest in open
seas in the tropics, it is lower near coasts
and after heavy rain, and it is at its lowest
near the poles (due to the influence of
melting snow).

DENSITY
In marine aquariums, it is not the salinity
of water which is measured, but the density
(often expressed as specific gravity,
S.G.), which can be calculated

WATER, A HAVEN FOR LIFE

PEAT
Peat derives from the decomposition of vegetation in an acid environment lacking in oxygen.
This process, which lasts several centuries, gives rise to a peat bog from which compact,
fibrous peat can be extracted. It endows water with both a yellow amber color and acidity, which
gives it slightly antiseptic properties. This means that some diseases are less common in acid water. The use of horticultural peat, which often has been enriched with various products, must be avoided in
favor of the peat for aquarium use that is commercially available. Boil it for around 15 minutes before use.

In the Amazon region of South America, the color of the water anges from amber yellow to brown, due to the leaves and branches floating in it. In an aquarium, peat can be used in the filtering equipment to reproduce the characteristics of this type of water (low hardness, pH under 7, coloring).

TURBIDITY

The turbidity of water refers to the presence of suspended matter - either living organisms forming plankton (rare in an aquarium) or inert matter, such as animal or vegetable remains or particles of sediment,particularly mud.
The size of this suspended matter ranges from a few thousandths of a millimeter to
several millimeters. In calm, unstirred water it forms sediment at a speed in proportion
to its weight. In running or turbulent water, some of the matter remains
permanently suspended, giving rise to more pronounced turbidity.
In aquariums, where the water is always in motion, systems of varying degrees of
sophistication (see Filtration, page 237) allow fish keepers keep their water clear.
The effects of this are entirely positive:
- the visual appearance is improved;
- the light required by the plants penetrates the water and reaches them more easily;
- there is less risk of disease, particularly in the fishes' branchlike;
- there is little sedimentation on the base of the tank, reducing both the possibility
of any warping due to excessive weight
and the decomposition of organic matter

FRESH WATER FILTERS

This type of water is also known as Continental water, a more accurate term from the
scientific point of view. Continental water accounts for only 2.6% of the Earth's water, the
rest being made up of seas and oceans. Of this volume, 98% consists of sterile water, in the
form of glaciers and underground water, leaving only the water of rivers, lakes, and ponds
as shelter for living organisms- barely 2% of the total volume of Continental water

TEMPERATURE                                          
An important parameter for aquatic life,
the temperature regulates the growth of
animals and plants and exerts an influence
not only on oxygen levels but also on
many other factors.
Whereas mammals have a regulated and
practically stable internal temperature,
that of fish and other aquarium creatures
varies according to the temperature
of the water around them. They
can survive only at certain temperatures
and some species are more sensitive than
others to variations in this parameter.
The temperatures of fresh tropical waters,
ranging from 20 to 30°C, are characterized
by less significant variations than those
found in temperate regions. In some
places the shade provided by the tropical
forest cools the water, while in calm water
the temperature goes up under the direct
influence of the sunlight.
The mean temperature most often recommended
for aquariums is 25°C, and variations
of 1 or 2° are of little consequence.
Fish are even capable of withstanding
even more significant variations for brief
periods (under 24 hours). On the other
hand, their metabolism (i.e. their general
bodily functioning) is in danger of serious
disturbance over any longer periods, and

be noted that excessively low temperatures
sometimes favor the development of
certain diseases.

OXYGEN AND CARBON
DIOXIDE
Since air contains around 20% oxygen,
even the most oxygenated water rarely
contains more than 1% dissolved oxygen.
Fish have special organs - branchiae -
which allow them to extract most of this
(see Anatomy and Biology, page 42).
Oxygen contributes, in
addition, to the respiration
not only of
plants but also of
organisms which are
invisible to the naked
eye and often forgot

Biological filtration and the nitrogen cycle

Proper management of the nitrogen cycle is a vital element of a successful aquarium. Excretia and other decomposing organic matter produce ammonia which is highly toxic to fish. Bacterial processes oxidize this ammonia into the slightly less toxic nitrites, and these are in turn oxidized to form the much less toxic nitrates. In the natural environment these nitrates are subsequently taken up by plants as fertilizer and this does indeed happen to some extent in an aquarium planted with real plants.

An aquarium is, however, an imperfect microcosm of the natural world. Aquariums are usually much more densely stocked with fish than the natural environment. This increases the amount of ammonia produced in the relatively small volume of the aquarium. The bacteria responsible for breaking down the ammonia colonize the surface of any objects inside the aquarium. A biological filter is nothing more than a chemically inert porous sponge, which provides a greatly enlarged surface area on which these bacteria can develop. These bacterial colonies take several weeks to form, during which time the aquarium is vulnerable to a condition commonly known as "new tank syndrome" if stocked with fish too quickly.

Aquarium filters

Aquarium filters are critical components of both freshwater and marine aquaria.Aquarium filters remove physical and soluble chemical waste products from aquaria simplifying maintenance. Furthermore, aquarium filters are necessary to support life as aquaria are relatively small, closed volumes of water compared to the natural environment of most fish.

Public aquariam

Most public aquarium facilities feature a number of smaller aquarium, as well those too large for home aquarists. The largest tanks hold millions of gallons of water and can house large species, including sharks or beluga whales. Dolphinaria are specifically for dolphins. Aquatic and semi aquatic animals, including otters and penguins, may also be kept by public aquaria. Public aquaria may also be included in larger establishments such as a marine mammal park or a marine park.

Salt Water Aquarium

Aquarium may be grouped by their species selection. The community tank is the most common today, where several non-aggressive species live peacefully. In these aquaria, the fish, invertebrates, and plants probably do not originate from the same geographic region, but tolerate similar water conditions. Aggressive tanks, in contrast, house a limited number of species that can be aggressive toward other fish, or are able to withstand aggression well. Specimen tanks usually only house one fish species, along with plants, perhaps found in the fishes' natural environment and decorations simulating a natural ecosystem. This type is useful for fish that cannot coexist with other fish, such as the electric eel, as an extreme example. Some tanks of this sort are used simply to house adults for breeding.

Aquarium classifications

From the outdoor ponds and glass jars of antiquity, modern aquaria have evolved into a wide range of specialized systems. Individual aquarium can vary in size from a small bowl large enough for only a single small fish, to the huge public aquarium that can simulate entire marine ecosystems.

One way to classify aquarium is by salinity. Freshwater aquarium are the most popular due to their lower cost and ease of maintenance. Marine aquarium require more complex equipment to set up and maintain. Along with fish species, marine aquarium frequently feature a diverse range of invertebrates. Brackish water aquarium combine elements of both marine and freshwater fish keeping Fish kept in brackish water aquarium generally come from habitats with varying salinity, such as mangroves and estuaries. Subtypes exist within these types, such as the reef aquarium, a type of marine aquarium that houses coral

Another classification is by temperature range. Many aquarists choose a tropical aquarium because tropical fish tend to be more colorful However, the cold water aquarium is also popular, which may include fish such as goldfish