Please research the fish before buying them and read up on the freshwater articles in the beginner's section which is linked in the left navigation under Beginner's Guides. From: Jodi - Cloudy Aquarium Water after water change I have 50 gallon column freshwater tank that has been set up for 5 months. 2 balas, 4 clown loaches, 2 silver dollars, 2 dojo loaches and 4 zebras.