We have a general rule of thumb for feeding fish here at Nelson’s and it requires some trial and error. During the spring and summer months we suggest feeding your fish once a day or once every other day what they can eat in 3 to 5 minutes. Remove any remaining food at the end of 5 minutes with a net. It will take some experimenting around to figure out the correct amount. Koi and Goldfish do not have “true” stomachs and much of what they eat will become waste (aka poop) that can contribute to algae growth. This is why it is important not to overfeed your fish even if they beg for more food, in the end it will only cause your pond to get algae.