I had 750 in a 625 gallon tank ranging in size from 2" to 8" (mostly 2" to 4"). I started developing serious water quality issues after 2 months. I've read that with a proper set up you can raise 1 lb. of tilapia per 1.5 gallons but about 1/4 that rate would be max for a non-pro.



"The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge." Stephen W. Hawking