You want to get a feeding ring/tube, which is going to be the best solution if you have an overflow skimming the surface of the display tank. Once the fish figure it out, they will be at the bottom of the tube waiting when the food comes out. I use one with my auto feeder and almost nothing makes it more than a few inches out past the bottom of the tube...
Something like this or similar
The AquaMaxx MFR-1 Magnetic Feeding Ring is an effective and simple way to reduce food going into your overflow, and more into your fishes` mouths. Drop any of your fishes` favorite flakes, pellet, or freeze-dried food into the feeder and walk away. Let the water do the rest; eventually, the...
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