literally stick them in a jar, add some java moss. Change half the water or so every few days or so, add air stone if you want.
I borrowed a 20 long from a buddy to work on some stuff. I took a few gallons from my main tank and put it in the 20. I did what I needed to do then let it sit for a while. I was going to use it as seed water fro the 55 Ive been working on.
Well long story short when I FINALLY went to empty the thing there was this beast moving around inside. Apparently a baby pond snail must have been sucked up in the water and transferred. It was near the size of a DIME when I pulled him out. He was so large I actually put him BACK in my main tank to re establish some sort of colony (for feeding my puffers and yoyo [RIP] )
Anyway these things are tanks and will survive a lot so long as there is food, air and clean water. The only thing I have found they are overly sensitive to is calcium loss. I literally lost my entire colony in my main tank. I noticed all their shells turning white and found out it was the PH balance I was using. That and pretty much all my fish were trained to eat them at that point.