Okay. I screwed up...."My tilapia are starting to suffer and no matter how many water changes I do I can't seem to get my Nitrites down. I have peas, beans, yellow peppers and lettuce growing (14 plants) and duckweed.

I have recently increased the amount of feed they're getting because they're approaching 4 inches. "
But in going back and rereading it, I think I found a MAJOR contributing factor to what is causing this....the increased feed.

To answer your previous posts, I don't grow anything off the salted tanks during winter. I bring the tilapia in for wintering over, and overstock them in 330 gallon tanks for the winter (+/- 2 months) Then start moving them back outside. The catfish, sunfish, bass, etc stay outside year round. My prawns are harvested end of every summer, and I purchase post larvae or juvies in early spring. They are a 4-5 month crop for me. Hope that clarifies.