I set my 600gallon freshwater tank up Sun 10/4/15, My Amm. Spiked to 0.081 I have a cont monitor on the tank Nitrites have stayed at 0 nitrates have been 0-5 I have a 24gallon a day drip on the tank. current stock 1 Arowana about 9 inches, 2 Jacks, and a full grown Rec Stingray. My Stingray is eatting great however the fish are only eatting a bit or 2 every few days. Any sugestions. Also once stable my husband realy want an eel is there any fresh water eels that would be compable with stingrays we plan to add 2 moto and maybe anther rec once the tank is stable.