At first, I measured out the pellets. But, after some discussion with my vet and doing some research, the pigs really just eat what they need (at least mine do). Overeating is never really a problem with pellets for me. However, I keep up with measuring the amount of fresh veggies to give them and make sure not to give them too much.
I have a satin pig, so I always worry about her weight because she likely has weak bones. Make sure you monitor their weight to be sure they aren't losing/gaining weight than is healthy.
I wouldn't want to bet on a guinea pig only eating what he or she needs. You'd be better off to measure out 1/8-1/4 cup of pellets daily per pig. If they don't eat all of them, great. If they do decide to eat all of their pellets some days, you don't have to worry about them over eating.
Okay then maybe I need to change something. My guinea pigs get unlimited Oxbow pellets. I refill it maybe twice a week...? They aren't over weight from what i can tell. They are about 2.3 pounds. They have had unlimited pellets all their life. Should i cut back to what you suggest for two guinea pigs? I don't seem to have any problems. Oh and Pinster sorry that I've kinda hijacked your thread.
Don't feed unlimited pellets, this can lead to a chubby piggy. I would make sure they get about 1/8 of a cup per day per pig, I would give seperate feeding bowls for a while so they can get into feeding habits and so they get their own fair share.
I feed mine 15 grams of Oxbow pellets per day per pig, this will normally last them until their 'dinner time' at 5pm, I've never had any left in their bowls after that time. I would never consider free-feeding them the pellets (mainly because I'd go broke in record time!) as they should be grazing on hay instead.
I have 3 piggies and they always have pellets available -but never finish them. After a day or two, I dump and refill (about a handful in each side of their dish). I'd think they'd eat more,but rarely is it all gone. This morning, one side was gone but the other side wasn't.