I just wanted to add that here in Florida, the tadpoles and bugs are so prevalent that my goldies don't get fed at all during the warm months. If I think about it, I may toss in floating pellets a couple times a month....but they are all
growing and thriving on bugs, larvae and tads.
In the winter time, outside goldies go into a form of hibernation and once the water drops below about 55*f, you should stop feeding all together. Their metabolism slows and they are unable to digest foods...so it just adds more decomposition to the water.