fish actually can be stunted in their growth based on the size of the tank.........this is unheathy for them and stresses them out. The only other comment that I am going to make is that Bala Sharks like to be in a group of atleast 2, preferably 3. They also like to swim alot and IMHO should not be in a tank smaller than 125 gallon assuming that you have 2 or three of them. The reason for this is that Bala's can and most will get up to 14 inches in size.