I have 2 male piggies, they lived in a 2x4 c&c cage, and they began to fight. so i separated them and now they live in a 2-story hutch one pig on each level. One of the two seems very lonely, the other seems to be loving live alone. I was thinking of maybe getting the lonely pig a friend? (with spaying and neutering)
Hi and welcome!
It is great that you care about your boys. Boars go through a very hormonal phase as teenagers, which lasts about from 4-14 months of age before they turn into more settled adults around 15 months of age.
To understand what has gone wrong and what all your options are, you may find this thread here helpful:
Boars: Bullying, Fighting, Fall-outs And What Next?
The best way to find a suitable companion is via a good standard rescue, as they will help to find a suitable companion, but are usually willing to either bond at the rescue or take a piggy whose bonding has failed back, so you are not going to end up with more piggies that don't get on. Please consider getting a companion for both boars. Even when they are not getting on living together, guinea pigs still need constant stimulation from their own kind through the bars.
if you want to go down the cross gender pair route, only one of the guinea pigs needs to be castrated or spayed. It is usually the boars that are neutered, as spaying is a much more invasive and expensive operation. Please be aware that boars need a full 6 week post-op wait until they are 100% safe to go with sows. I have the daughter of a supposedly safe over 5 weeks post-op boar (not one of mine) living with me, just to prove the point that it can really happen that late! it is also important to find a good vet with either practice in guinea pig neutering or small furries operations in order to minimise any post-op risks. We can provide you with tips and support during the operation and post-op recovery if you wish, just open an ongoing support thread in our illness section. However, neutering is not cheap in the US, especially in your part of the country. Perhaps you may want to talk it through with a more local rescue? they may also be able to give you tips.
The advantage of male-female pairings is that once acceptance has happened, fall-outs are very rare. A single boar can live alongside sows with interaction through bars, as long as you secure the cage, but never two full boars; they should ideally live above or well away from sows as to not be upset by female pheromones.
Here is a link for recommended good standard guinea pig rescues in your state :
Guinea Lynx :: US Guinea Pig Rescue and Shelter Organizations
And this is the Guinea Lynx link for recommended vets:
Veterinarians New Jersey - The GLX-Files