Great post, as im having problems with this too.
I used to keep mine in a litter tray, but found that they were using it as a litter tray rather than a sack bar. I found that they liked to sit in their sleeping area and eat the straw, so ive changed that to hay instead and they eat it but it gets all trodden, wet and soiled.
I bought hayrack and found dolly sat in it the next day, i was worried she would hurt herself. She sat eating the hay and used it as a toilet. Unless they are actually in the rack themselves, they dont seem to know how to use it. :?
I use one of these:
http://www.willowwarren.co.uk/proddetail.asp?prod=largehayracks
one of these:
http://www.willowwarren.co.uk/proddetail.asp?prod=hayballs made to measure in a huge size of unpeeled willow because Poppy can chew through the standard one in a few days! :roll:
and one of these:
http://www.willowwarren.co.uk/proddetail.asp?prod=advancedroundfeeder which is simply the best invention ever! 360 degree acess and the weaved base keeps all the dust/hay off the floor underneath and damp out if using during the day outside.
Me and the buns love all of them
These are all great, but they arent Dolly proof, she destroys wicker in minutes. Great fun to watch, but it starts to get expensive! :lol: She can also climb inside most of these too and then Marley cant get access. :roll:
...
I have tried a few things, they could work for you but there are some really good suggestions already.
Ive tried:
-fat ball feeders, like what birds use with big holes
-packed into various toys, cardboard boxes, toilet roll tubes etc
-veg to balls (the metal ball that you put veggies in and hang up) but its quite small and youd need a few that would have to be refilled a lot.
-plant pots
-tissue boxes
-a number of different hay racks
The guinea pigs manage everything, but the buns just seem to climb, poo and play rather than eat! :roll: