I have 2 Jack dempseys, one female one male. I had the female first and I really enjoyed watching her swim around. By chance I found a male dempsey at the pet store and decided to take a chance and see if they would get along. Well it seems they get along really well they never leave each others side, however after having them together for about 3 weeks the all of the sudden started hiding and being very afraid when i come close to the tank. Any ideas to why my fish are so frightened????