It's best to wean your fishes off of the feeders (hopefully, you're not feeding your fishes goldfish or rosy reds, as they really are poor choices nutritionally, and they can cause health issues down the road, generally Thiamine (B1) deficiency and incorrect HUFA's, which often results in CNS disorders (clamped fins, anorexia, seizures, early death, etc).
Once you wean the fishes, they will indeed get the hang of your feeding style, and will generally wait their turn IME with lionfishes, altho fuzzies are kind of a hopeless case, LOL. The thing with fuzzies is they tend to crowd the surface at feeding time, so an eel might be OK in that instance.