[RackinRocky]

Now, this is just weird... I bought two guppies and one Turquoise Rainbow on the same day, and put them in a quarantine tank. This was about about 10 days ago. The guppies both died within two days. The Rainbow is being treated now for columnaris and is greatly improved.

Well, just now I was checking on her, and I saw something swimming! Thinking I was "seeing things," I looked again, and sure enough, two babies! I know that Rainbows have eggs. Would it be possible she laid eggs while in there? Or do they lay just while spawning? I'm inclined to think it was one of the guppies, but I had thought they were both males! Both had long, fancy tails. This is bizarre. Anyway, I netted them and put them in with my guppy fry in another tank. How they survived my 50% water changes, meds, etc. for over a week, I'll never know. Any chance they could be Rainbows?

 

[SeaHorse]

Wow Congrats!! Those are amazingly hardy little things whatever they are....
I'm guessing Guppy. Reason? The Rainbowfish do lay eggs and without a Male to fertilize them they would not hatch. I don't believe that they get fertilized in the fish. I could be wrong.
I have several Boesemani and they spawn all the time... but never any fry!! It's been months now. Now I do know several members on here that are very successful with their RBF spawning successfully. (I have a large Female Molly who eats the eggs and everyone just sits there and watches her do it, so no fry until I do something with her.)
You didn't get any new plants for that tank did you? They can come in with/on them if you bought plants and put them in.

Keep us posted and pics once they are big enough!

 

[RackinRocky]

Thanks, Jakiebabie. I have since done some research online, and the pics of Rainbow fry look nothing like what I found. The Rainbows are extremely long and streamlined. These look just like my guppy fry. Oh well...even though I suspected as much.

This is a quarantine tank, with no plants in it, so no chance the fry could have hitchiked in. Maybe the one guppy (half black) was really a female? The anal fin looked like a female's to me, although the fins were quite long. I guess some female gups have longer fins? So it might well have been that fish. In any case, they are about the same age as my other fry, as they are all very close to the same size!

I bet you'd LOVE to get some fry from your Bosemani RBs! Maybe you can move your molly elsewhere so they have a chance to hatch?