hikisquid
sews all the things
The comet goldfish thing is absolutely true. I had a Senegal bichir that fed on comets for a long time to supplement her pellet food, and she was listless and just seemed lethargic all the time. As soon as I switched to a colony of self-bred (and gutloaded) guppies and fresh salmon, she perked back up and lived for quite a long time.