High Nitrates

[Yherbert]

I tested my tap water. Nitrates were present. Nitrates =20ppm.

 

[Yherbert]

You are so helpful. What do I now do?

 

[dalto]

Where does your water come from? Do you have well water or town/city water?

 

[Yherbert]

It's city water.

 

[V227]

Over filtration is good. A good rule of thumb is filtrate 2x the total water volume. The BB grows proportionate to the amount of available nutrients. The BB growth is limited to the amount of filter media available. Your 2 A.C. 110's BB are probably not maxed out with only 22 African cichlids, especially since your using a third filter. The extra filter offers additional water flow which will benefit your fish. The extra filtration expands the potential for additional
BB growth to handle the bio load if you decide to buy a Pacu, lol.
Coincidently, I also have a 120 gal. With 2 A.C. 110's. I do a 35 gal WC once a week, concentrating on thorough gravel cleanings. The hardscaping is designed to allow easy cleaning access. No water parameter problems. If your tap water is high in nitrates, realistically, not much you can do. If your cichlids are acting normally, chances are they have adapted to the situation and will be fine.

 

[Yherbert]

All fish are acting normal except one the Venusi. He's stepped up to becoming the tank boss.