Single random mystery fry

In the absence of any other replies my best guess (unfortunately the pics don't show it too clearly) based upon your existing stock would be a Rainbow fry.
As stated, it's a 'best guess' but based on several things it could be right. Rainbow fish lay adhesive eggs (which could have lodged in one of the plants you transferred) and the eggs don't hatch for up to a fortnight after being laid. It doesn't look like a baby Guppy and really is a bit too long to be from Tiger Barbs. It's also a bit the 'wrong shape' to be a Corydoras and Neon fry are so tiny as to be almost invisible, looking more like tiny slivers of glass so I'm putting my 50c on it being a Rainbow.

As to feeding it, this might be a real problem if you only have one in the tank (although it's not unreasonable to hope/assume that more eggs were transferred with the plant). You really need the finest of food for it/them but only the tiniest amount too as too much uneaten food might just mar your cycling process.

Having a snail in there might well be beneficial as it could help with uneaten food.

You could try crushing down a small amount of food, or if you can get it, Liquifry #1 would be a good starting point as they claim it breaks down to form infusoria which would be a good food for the tiny fish.

That just about covers what I can suggest - maybe other members could make suggestions?

Watch out for more fry appearing in the coming days too.

Hope that helps.

Oh yes - and welcome along.

John

I find the best way to post videos is to use the youtube route - upload it to there, then post their link.
John

Your video reinforces my suggestion - I'm even more convinced now that it's a Rainbowfish fry.

It appears quite 'well fed' too, must be getting sustenance from within the tank so I wouldn't go making a special trip for food just now. It seems to be doing OK on what it is gleaning from within the tank.
That's not to say you won't be needing food in the future - just not necessarily immediately.
As it grows (and they aren't the fastest of growers in the fish world) you should be able to finely crush a small amount of your regular food (I use a mortar-and-pestle) to feed it on if you can't get dedicated fry food locally.
Some advise egg yolk, I find this tends to sour the water too quickly for my personal liking but it's another option to be considered.

John