Gerbils chewing on plastic lid
We got my girls a Sterelite bin this summer and they seem to really like it. For a while we used chicken wire as a lid and just bent it around to fit snugly, but my dad was worried about either wearing it out or it bending too out of shape to fit properly (we were already having trouble getting one corner to stay down) so we cut a whole in the plastic lid and my dad attached the wire to the top.
The problem is they do chin ups and chew on the plastic (they used to sit on top of the water bottle and do it but I moved it up to stop that). They've made a lot of ....progree and I'm worried they'll eventually chew it away past the wire and make a hole they can get out through (not to mention it can't be healthy to chew on). How can I make them stop, ot am I just going to have to figure out a new lid solution?