I don't need to feed my pigs extra Vitamin C at all. They get it in their regular diet.
I make sure they get some bell pepper and lots of dark green leafy veggies plus I make sure to feed them a pelleted
guinea pig food that has
'stabilized' Vitamin C in it. The brand I use is Oxbow because they always put an expiration date on their packages for one year out from manufacture. It's easy to make sure that the pellets are fresh that way. Do not be tempted to use a different kind of pellet, since
GP pellets are the only ones that have Vitamin C.
Here at
GPC that's pretty much the way we do it. No one has to feed them extra as long as we follow the basic
GPC feeding guidelines.
Sometimes people do feed the pigs a little bit of Vit C tablets just for a treat though. Oxbow makes a Vitamin C tablet that you can feed your pigs if you are really worried about it though. They are hard to find and expensive though..