Overfeeding 1, but not the other?

[griffinej5]

I have 2 veil tail goldfish that I got last Friday. It looks like 1, the smaller 1, is getting too much to eat and it looked a little bloated, but this doesn't seem to be the case with the larger 1. I was feeding them flakes twice a day, what they could eat in 1 minute. The smaller fish, Goldeen, had some trailing feces today and yesterday, and also looked like it was bloated to me. So, last night I fed them peas instead of their food. Today I gave them a half a green bean and a tiny bit of raspberry. Goldeen was still chasing down a bit of green bean I missed removing hours later. Magikarp,the other fish, had stopped long ago. So,a few questions I guess. Is something else better as the base of the diet than floating flakes? Maybe something in combo with it? Is tetra ok? Am I doing something horribly wrong?
They'll be getting separated to eat most of the time starting in a few weeks. I'm going to start training them, so I'll need to make sure the one who is working gets the food. I suppose I will then have better control over who eats what.

 

[bruinsbro1997]

Are the veiltails some sort of fancy type goldfish? Either way I'd reccomend sinking pellets, especially for mishapen ones like fancies.