I have a 60 gallon tank right now there are 5 clown loaches ranging in size from 6" to 3", 1 4" Yasuhikotakia modesta(blue botia), 1 4" angel fish, a bristlenose pleco, and 7 guppies. I had 15 guppies, over the last month they have been slowly but surely disappearing. I have stripped tank of all decor a few times after a disappearance to find no signs of the guppies in the filters or on the floor(sealed top on tank). Yesterday another disappeared so I again stripped tank and this time I found a small piece of skin with a tiny bit of meat still on it! I feed the tank a variety of food alternating between brine shrimp, blood worms, flakes, and pellets. All water parameters are also spot on 7.1 pH 0 ammonia nitrite and nitrate also great. Any ideals? I think they are being eatin but can't find anything on this. Thanks in advance for your help