I just picked up a 8" black pacu. He's eating like a pig and i know they get real big, real fast. He's in my tank with mid size fishes. A red devil chiclid(7in), silver arrowana(12"), a giant gourami( 7in") , frontosa cichlid(7in), a huge rosequeen( 12") and 4 red parrot (3in). The tank is a 500G hook up to a 125G sump. I have an Eheim filter but its not in use. I use the porous rocks as natural filter roughly about 200lbs. I also use small filters bag to catch debris /waste. Usually I change about 150G of water every 2 wks. Is that enough? thanks
