- Have you tested your water?
- Yes
- If yes, what is your ammonia?
- Very low and not relevant to this question
- If yes, what is your nitrite?
- Low and not relevant to this question
- If yes, what is your nitrate?
- Very low and not relevant to this question
- If I did not test my water...
- ...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.
- Do you do water changes?
- Yes
- What percentage of water do you change?
- 41-50%
- If I do not change my water...
- ...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.
I'm treating my tank currently as I have some fish with what looks like cotton on their mouths. The directions say to remove activated carbon from the filter. The cartridges are over two weeks old. Do they still need to be removed or should I leave them in for better filtration? These are the cartridges I have.

