Both corys and kuhli loaches need to be in groups. Especially the kuhlis. If you get one kuhli you will never see it because it will always hide. If you have 6, they will be out exploring much more. As for the food, there probably won't be only one food that all of those fish can eat, because the middle and top swimmers will eat any flake or pellet food that doesn't immediately sink and the bottom dwellers won't get any. Because of this, it's necessary to feed a flake food in combination with sinking wafers. I really like omega one. My "staple" for my tank is the omega one veggie flakes (most of the fish I have are omnivores and it's good to have some veggies in their diet, although if you read the ingredients of the veggie flakes they're really not very different from the regular omega one flakes- I think the first 3 or 4 ingredients are still the same) and I also feed 1/2 of an omega one veggie wafer and a couple omega one shrimp pellets. This what I feed on a "regular" day. I like to alternate every couple days with some of my various frozen foods supplemented with a cooked, de-shelled, smashed pea.
