Cories are shoaling fish and must be kept in a group of at least 6 with more being better. They should be fed sinking pellets, and should not be left to eat food the other fish don't eat. They also need a sand substrate.
There should be no uneaten food in a betta's tank. They should be fed a small number of floating betta pellets per meal (the actual number depending on the size of the pellets and the fish), and if they are anything like my male betta, he waits at the surface as I drop each pellet in the tank one by one and he eats them so fast its almost like he's inhaling them. He always wants more than it is good for him to have. There is never any waste with my fish.
If you have left over food with either your male or female, you are feeding them too much.
There should be no uneaten food in a betta's tank. They should be fed a small number of floating betta pellets per meal (the actual number depending on the size of the pellets and the fish), and if they are anything like my male betta, he waits at the surface as I drop each pellet in the tank one by one and he eats them so fast its almost like he's inhaling them. He always wants more than it is good for him to have. There is never any waste with my fish.
If you have left over food with either your male or female, you are feeding them too much.