Has any1 heard anything about how the bedding will stop the colony from breeding?

I've been using the softwood mix from PetCo for quite some time, but just recently, my 1.4 stopped breeding altogether. I now have only one tank actively breeding and raising a (single) litter. The last litter from it is at the small size.

(However, of the 9 fuzzies in this litter, five are albinos, and I don't have a clue which to keep back to try and line/outcross for more albinos---they were an accident.)

I'm at the point where I'm still feeding them faster than they're breeding. If I go to the 45gal (or larger tanks I have) and do a 1.8 or 1(2?).12, would that be happier and more of a natural colony and they'll breed better???

They're currently 1.4 in two different 20g tanks, wheel, softwood bedding, and the pig feed (Mike C's post), getting kitten food occas when there are babies being nursed.

Thanks!