I have a 40 gallon wet/dry acrylic system with three goldies. I have a question about feeding them. I bought the ProGold food for them, and they like it, that is, when they find it! It's hard to capture their attention all at once, and food can literally fall on them and they miss seeing it. The problem is, I put a bunch of black river rock on the bottom, ( I didn't want small gravel to get stuck in their mouths) and the food gets trapped underneath the rocks where they can't get to it. Do I have to have a bare bottom tank to feed these guys and keep a clean tank at the same time? I feel like I need to do a water change every day! I also am having a hard time telling exactly how much my guys are eating. Help!