I'll send you a few pounds of them if you cover postage... 
Little buggers are very handy, but if you overfeed your fish by one flake of food a week, you'll have a lot of MTS. Still, I'm quite glad I have them, they work the substrate quite well.
Little buggers are very handy, but if you overfeed your fish by one flake of food a week, you'll have a lot of MTS. Still, I'm quite glad I have them, they work the substrate quite well.