YaY I can't wait to see pix of the final tank :)
Is the Tetra tank a kit? Or just the tank? Make sure the filter with it is rated for a 10G...I bought a Tetra 16G Tank Kit, and guess what..the filter was BELOW rated for the size (what the heck??)..had to buy a new one!
I'd shop around a bit though, people moving and stuff might give you a nice set up with
extra goodies for less. :)
Some people say they should all be the same size, others disagree...Some big ones
are gentle & some tiny ones are drama queens LoL
It's just a roll of the dice really...When you do finally introduce them,
pick a long weekend when you can keep an eye on the action.
I picked ones who looked wiggly & active...Its tempting to get a sicker looking one,
but chances are she's too weak to fight for her place in the tank & could die from stress.
If you get them all from the same person or place, I don't think you need to QT them.
Maybe some people here will sell or adopt out a few to you :)