About a month or so ago, maybe more, I hatched some brine shrimp eggs to use the brine shrimp as goldfish food. Most of the eggs didn't hatch. Then the little things stopped swimming around until I couldn't see any movement in the tub at all. I considered it a total failure, thinking they had all died, and forgot all about it.
Anyway, I just realised that I have eight or nine live brine shrimp varying from about 0.5cm to 2cm long in my tub. I haven't done anything to the tub in weeks. No food, light or heat. I no longer have my goldfish so they cannot become live food. What the hell do I do with them? I have a betta but I am assuming brine shrimp of this size will be too big as food for my betta? So I guess that means I'll have to keep them as pets. What do they require? How big do they get? etc etc.

Here's a site that has a whole MESS of info on brine shrimp. It's a little close to tl:dr status, but it has everything I could think to list and more...

http://web.cecs.pdx.edu/~davidr/discus/articles/artemia.html

For some reason, the link is not working for me.

I think your betta will happily eat the live brine shrimp, even the big ones. He'll just rip them apart.

Odd, and I went to it, and now it doesn't work for me either.

http://www.waynesthisandthat.com/shrimp.htm

Try this one, I think this guy specifically raises his brine shrimp to be fed to bettas.

Sorry about that previous link!