Let me add. . .
>> Especially if you make a Gerbilarium for them. They can go without being cleaned out for a couple of months. So in that time you should be able to convince your son to clean them out! ;-) Even going that long, the only smell is the smell of the peat.
I find I have to clean out the animals to avoid smells in the following order of smell:
Guinea Pigs (indoors): every other day.
Rats: Every two days.
Jirds, Degus and Hamsters: Once a week
Rabbits & Guinea Pigs (outdoors): once a week.
Gerbils: Once every two months. <<
GP's EVERY OTHER DAY?? Give me a break. I use Carefresh and my two get cleaned out once a week and they are just fine. As I use five dollars worth of the stuff each week I am not doing it every other day - a half hour operation.
Gerbilariums. I doubt if many people could use it right. I clean my aspen-bottomed tanks one every two weeks even if there is no smell as it is more hygenic and keeps bug problems at a minimum.
Oh! I just realized. One gerb who developed an allergy to aspen half a year ago now does NOT have that allergy: I forget a few months ago and put her back on aspen, and she is fine. Odd.