I was just getting around to starting to hatch another batch of baby brine shrimp for some baby corys and guppies. The corys are from eggs laid in my 55gal that is primarily for various rainbows. I didn't do anything to initiate it. I'm not even sure which species of cory they are, most likely aeneus or paleatus. There are some trilineatus in there as well.
But I scooped some water from a breeder tank into the Ziss 'blender', added the salt and was about to sprinkle in some brine eggs which I noticed a bunch of tiny fry. Good thing I hadn't gotten around to dissolving the salt.
They are Boesemani rainbow fry. I had a male and two females in the breeder tank for about a month and never saw any eggs. Though I never checked the spawning yarn. I think it has been more than a week since I put them back in the 55. Maybe there had been more than were eaten as soon as they hatched. There was only a juvi albino bristlenose left in there to keep the brown algae in check. I was going to move on to breeding something else. That bristlenose is one of a bunch of babies I returned home to find in my 125 gallon after two and a half weeks of traveling in June.
I also have two juvenile rainbows of some sort that resulted from two species got at the April auction and had in the same breeder for quarantine. Weeks after I moved the parents into the 55 I noticed the fry in there, only a few though. I've got a lot more this time. One of my surviving juvi rainbows I had put in large cooler in my backyard that has all sorts of little critters growing in it. Since I was going to be away I wouldn't be able to properly care for it with small food. A couple others I kept in a 5 gallon tank I use for daphnia. That ended up working out alright.