Fantail goldfish and african dwarf frog

Question
So I just bought my second aquarium today [10 gallon], and it houses 3 fantail goldfish, an Oranda, and an african dwarf frog. I have 5 live plants in there and they seem happy with it. They're currently about an inch long. I was wondering how large of a tank I'll eventually have to get, and if it's normal for them to slightly nip the frog. I'd be terribly upset if anything happened to my little frog, so hopefully within a day or so it stops. They don't seem to do it hard but I'm sure it's still uncomfortable for the frog. Also, they're HEAVY eaters, so how can I ensure my froggy gets fed as well? Thank you.

Answer
I would be more concerned with what your water chemistry is going to do. You got the new tank today and fish too?... The tank water is suppose to cycle before you add fish.  The water chemistry is going to spike and you are quite possibly going to see fish loss.  In the mean time you are going to need to change at least 20% of the water each day for the next four days and then get your water tested.  I wouldn't mix the frog and the goldfish because goldfish never stop looking for food and it will be very difficult for the frog to get fed.  Eventually you are going to need a 30 gallon tank for the goldfish as the rule of thumb is one goldfish per ten gallons of water. As to feeding the frog... if you have sinking pellets or something for him to eat you can sneak those in the tank while you feed the fish flake food that floats... he might get some of the pellets... I would give the frog many places to hide... they like to crawl under pieces of driftwood, etc.   keep me posted... dave