I run 2 FX5s, both with 3 trays of biomax, on my 220 and 10 mins after feeding the water is crystal clear again. If you forget the stingray, and even the knife, one FX5 loaded with biomax will be just fine. (I personally don't agree keeping rays in anything less than 3ft wide).
- http://www.tfhmagazine.com/freshwater/feature-articles/keeping-up-with-nitrate.htm
Wild caught fish are more sensitive to nitrates than captive bred fish.
Yeah, he is in my 220 with a Tems, Orino, Indo Dat, 12 Red Hooks, Spotted gar and some fancy plecos (Xingu Gold Nugget, and Leopard Frog). He is already eating pellets, and is more afraid of me, than other fish. Haha