Now is the time of year when the aphid numbers are at their highest - feeding on terrestrial plants before predator numbers catch up. I collected quite a few from one of my fruit trees, and just put them into the fridge. What do you guys feel about feeding aphids to fish? Is this safe or do some fish fall ill? Feeding ants to fish is a bad idea due to the high concentrations of formic acid. Are there any risks like this?