I have the two in a 125 gallon tank, along with two oscars (one medium, and one small) and one small jack dempsey. Every time I try to feed the eel and rope fish the oscars and jack dempsey eat their food. I try to feed them earthworms and beefheart. I tried hiding the food under some driftwood, under the gravel, and behind things, but they keep finding it before the eel and the rope fish. What should I do?