Ah, thanks you Torphaine and Francis for replying.

Ya, I learnt the hard way with the alpha female thing. My first litter had 6 but didn't know that other females aren't allowed to breed so that litter became 3. The book I bought wasn't very informative for me. Anyway, I now house them in suitable pairs, each have their own 2ft tanks and lots of toys. Only one gerbil will use the excercise wheel hehehe.... I also learnt the hard way with tanks. I went and bought a CriterTrail 2 tier cage, the petshop said suitable for gerbils but in the end, some parts were chewed away by my gerbil. Now they are housed in durable plasic aquariums

For feed, I give them a hamster staple diet. Is it ok? Can't seem to find one just for gerbils. Also, what can and can't be given to them? I occasionally give them a small bit of apple. I'm still learner as this is my 1st time with gerbils and I could be the only person in my area with 8 gerbils. So far, no petshops sell them. I have searched high and low for them.