I have a 300 gallon tank with Arrowana about 15 inch large oscar, parott, 2 clown loaches 4 or 5 large cichilids the tank has been up for about a year now. I only have 1 500 gallon pond filter from lowes, that I change about once a month. I installed a 1/4 water line and hooked it up to a inline water filter from lowes that I attached a drip addmitter to and drilled a 3/8 drain line at the water line i wanted. tank always crestaly clear and almost no work on my end. I also have an air wand in the take as well