I've read that goldfish will eat spinach. It sounds like a lot of people get fresh spinach and boil it or whatever. Can I feed my goldfish frozen spinach that's been thawed/cooked?

Also, could I feed my goldfishes raisins?

spinach and raisins should be okay as some of the members here uses grapes

You can certainly feed them frozen spinach. Just thaw it out and tear it into little pieces and feed. You don't even have to cook it, since frozen spinach has been blanched (lightly cooked) before freezing.

As for raisins, I have never tried them.

Ewww. Lol I dont feed my fish anything I dont eat my self.