Flower1982 said:
I suppose I could move the betta fish to his own tank. But he seems happy in there. The betta fish doesn't bother any of the other fish. All the fish get along. Well the 10 gallon tank I have was my first fish tank. I'm still learning more about fish keeping. I got the 30 gallon tank to keep my goldfish in for the winter. During the summer they are in my 80 gallon container pond. I'm hoping to get an inground pond maybe next summer or the summer after that. So I could keep my goldfish outside year round.
Goldfish can survive in nearly completely frozen water. Unless that 80 would freeze solid, I would not worry about the Goldfish outside over the winter.
No on the shrimp, with those fish, IMO.
Oto's mostly want algae. I don't think they go much for old fish food, but I sure don't have any evidence to back that up.
There
are pygmy cories... A Kuhli Loach or two might do a great job for you too, as they not only would eat much of the food that hits the bottom (they come out mostly at night though, if they have places to hide during the day), but Kuhli's also eat detritus (fancy name for poop)... and with your tank inhabitants, you probably have a bit of that.