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.