Newt: You’re listening to The Sound of Science on WNIJ. I’m Newt with NIU STEAM.
Becky: And I’m Becky. Have you noticed that the water in your fish tank is cloudy even after a good cleaning?
Newt: I wipe the glass, refresh the water, and put all my plants back in place. And it looks dirty again very quickly. Why is that?
Becky: Well, Newt, it’s because you interrupted the nitrogen cycle. Your tank is its own ecosystem to maintain balance. All fish tanks contain a delicate combination of ammonia, nitrites, and nitrates. We need to clean our tanks to keep things hygienic, but changing the water or filter can upset that balance. If the combination is too far, everything becomes harmful.
Newt: I know ammonia is a byproduct of digestion and excretion. But what are nitrites and nitrates? Where did they come from?
Becky: Ammonia can also come from dead material, living plants, and uneaten food. This is the most toxic part of the nitrogen cycle, but ammonia turns into nitrite and finally into nitrate. Each step of the cycle reduces the level of toxicity in the fish. Although nitrates are much less toxic than ammonia. If any of these are too high, the fish may die.
Newt: What can I do to keep my fish healthy?
Becky: The most important part of tank hygiene is maintaining nitrogen circulation through your cleaning cycle. It’s best to start this process before you add fish, but it’s never too late to improve the lives of your little friends. A water conditioner and bacteria are added to the water to start this process. Add some food and let the tank water rest for at least a month to start the nitrogen cycle.
Newt: It’s safest to test the water before adding fish. Of course you’ll want to check different parts of the nitrogen cycle, but you’ll also want to check pH hardness and alkalinity levels. After using your water properly, only change 20% of your water when cleaning.
Becky: Don’t overfeed your fish either, because uneaten food can increase nitrogen cycling and throw off the balance.
Newt: It was WNIJ’s The Sound of Science, learning something new every day.