Health & WellbeingMy Fish Stay at the Bottom of a Clean Tank, Are They Ok?
Cleaning the filter and changing the water may have upset the nitrogen cycle in your tank. This is due to removal of beneficial bacteria which convert ammonia (from waste, food, urine, etc.) to nitrites. Water and filter changes can be stressful as well. If you have the means, test your tank water for ammonia, nitrite, nitrate and pH levels. Adjust accordingly using conditioned water or additives that will bind harmful compounds. You can also submit a water sample for testing. Moat pet stores or professional aquarists will do this for free or for a nominal fee.
Updated on September 24th, 2025