Originally posted by shellonabeach
TM,

As you know DO NOT use material like rags for hamsters and gerbils - if chewed and swallowed it will cause an internal blockage. Gerbils chew everything and hamsters pouch stuff - fibres can get stuck in the pouches or around the large incisors etc. Many hamsters have died from being kept on fibrous substrates, such as the fluffy cotton bedding sold in petstores.

I would suggest you try paper based cat litter for all of them (won't be much fun for the gerbils but until you get tested that is best) this will absorb the urine well. It is however not very soft so you will still need to give them shredded toilet paper to nest with (but not so much). Or a wood based cat litter (as long as it is not pine or pine scented).
OMG your right! Thanks for pointing this out so fast. I have never had a gerbil and forgot they have pouches. I asumed it might work. I had also thought of the cotton, never thought it would be bad for them. again thanks for correcting me. I have learned some thing