I went into the pet store today and bought a fish off the employees info. I was wrong I should have looked into a fish before I bought it. I bought a dragon fish. I have a 125 gallon tank with 1 Oscar 2 jack Dempsey 1 concivt and 1 pleco. the problem is I found out the dragon fish needs brackish water. and I don't have that. what should I do. should I bring it back to the store. or can the fish I have live with salt in the tank. I don't want to hurt any fish. I am in a stand still. if anybody can help me thanks