So I've Got A Spare 10 Gallon Tank!

[thebassmster]

unless you want the tetras to be a snack for the crayfish i wouldn't recommend it, for a crayfish you need a fish that is fast and that generally stays on the top of the water column crayfish are really neat and it's fun to hand feed them

 

[Autophysn]

nothing, set it aside for a hospital tank or, feeder tank

imo