Hi I have a problem . I have a 55 gal freshwater tank. The fish I have are 2 upsidedown catfish, 2 playts, 1 irredescent shark, 3 yoyo loach, 1 weather loach, 2 kuhi loach, 2 sunburst gourami, 2 silvertip tetra, 1 pleco, 2 silver hatchet, 2 angel, 4 bumble bee, 2 tiger barb, 2 octocinclus algae, and disappearing large neons. One of these fish are eating the large neons. I had 1 neon that lasted when we started the tank, I purchased 8 more but they were pretty little they all got ate but 1, so I purchased 6 large ones, 3 were missing, the next day there was only 2 left but one was in the plants with a big bit out of it's stomach. WHICH ONE IS EATING THEM.