If you're just doing one cage/colony, a 20gallon long aquarium with wire mesh lid would probably work better. Most can be found for cheap in garage sales or the classifieds in your local paper.
If you do end up utilizing the above DIY method:
- I would get a larger floor spaced tub for more room to move around and decrease the crowdedness...
- Increase the hole size in the lid...
- Add a hell of a lot more bedding than what is pictured...
That thing has GOT to reek.

uke01:
Rodent health will go down when ventilation is greatly reduced. The more ventilation you have, the better their health and longevity will be. JMHO.