I already had the betta trained to come to the same corner of the tank for each meal (Everything that eats learns quickly where the food is
) I never threw away the cup he came in, because it turned out to be the perfect size for refilling my filter after a water change. I scoop him up in the cup and he gets his bloodworms there, and when he goes back in the tank he cleans up anything the frogs haven't eaten yet. I did this the other day and realized just how much he has grown. He has doubled in size since I got him, and he now almost touches the sides of the cup. He doesn't stay in there long, just till the frogs have eaten enough to get nice round tummies.
Future frog escapes have been foiled by a piece of plastic canvas over the gap.
The shrimp basically eat any left over fish food, so I deliberately feed a little more than my fish can eat so there will be some left for the shrimp. I also add an algae tablet every couple days since cherry shrimp are primarily algae eaters.
I got the shrimp because they were a pretty red, and thought I should have some scavengers. They are a lot more interesting than I thought they would be.