Can they eat potato peelings?  I think they probably would,  but would it be harmful?

Mine don't like potato peelings, i even tried sweet potato peelings which they also they don't like :) I am not sure if they are bad for them though. mine are ever so fussy, they love there stick of celery and chopped cucumber :)

I've never fed my guinea-pigs potato peelings, I've often read conflicting things about potoatoes and guinea-pigs so would not give them.

As well as hay and shop bought guinea-pig food they do enjoy:

grass, parsley, dandelion, carrot, apple, kiwi, alfalfa sprouts, celery, broccoli, sprouts, cauliflower, kale, spinach, cabbage leaves, peas, swede, tomatoes and raspberries. :-)

Mine go crazy for corn on the cob, it's a bit expensive so I buy it when it's been reduced.  I didn't know they could eat tomatoes though, will give them a try.  Mine also like strawberries and grapes.  I hope grapes are ok for piggies.

Have you offered them yellow peppers? They go mad for it. Dont give too much though.

Our guinea pig's love spring greens , and on the days they can't go out in the run i can be found on my knees in the garden with a pair of scissors cutting grass for them to eat !!!!!!!

Tomato is a favourite with our picky piggy. If you give her a variety of fresh stuff she'll go straight for the tomato every time.
We used to have a male that loved oranges.

My five piggies all love spring cabbage (dont like anything pale leaved!) They also love red/yellow peppers, carrots, parsley, celery, abit of lettuce though not iceberg. Oh and I heard you should not give them apple skin (especially baby gpigs) And of course they love dandelions and chickweed. Have never tried tomato either!
I have two guinea pigs that love the hay best and will always go to this first!

We used to feed ours PAH nuggets which have all the vitamins etc but they didn't seem to eat a lot of it , so we swapped to Tesco feed ( in the purple bag ) and they can't get enough of it !!!

Mine have just had a selection of carrot, cucumber, pepper and tomato.    They have left the tomato!  Still not sure whether to try the potato peelings, anyone feed their piggies these?

I have just read that potato peelings are poisonous to guinea pigs!

I have never fed my piggies potato peelings and dont intend to start now. I cant see them liking them when they get so many other nice things anyway and I had a feeling they could be harmful. Best steer clear.