Thanks Ria
. I put cardboard round the inside bars so it was about 5” up the bars. Cut up a few Amazon boxes to make the long strips and attached them to the inside of the bars with cable ties. You then need a lot of substrate - and fill the cage almost up to the top of the cardboard. This effectively reduces the height of the cage. Even then I am careful with the set up so if they did happen to climb to the roof and monkey bar snd drop - they can’t land on anything hard or sharp. I was a bit concerned about the ladder being fallen on so had something hanging above that.
Because the substrate is so deep, anything that isn’t very lightweight needs to be supported underneath or on a shelf. So easiest to stick with cardboard - for houses, tunnels etc. But if you do use a wood house you can just glue some dowels to the sides as stilts/legs to support it.
It’s a great cage for a smaller hamster if the height issue is resolved.
Attaching the cardboard took me ages but once that’s done it’s just setting a cage up as normal.
Only thing I would say is I would be cautious about the green shelf from that cage. It has little holes around the edge and I’d worry a smaller hamster could get a toe caught. I got a shelf from ranch house cages on eBay. It’s a nice solid wood one. It didn’t quite fit so needed a man with a saw to cut it a bit (and also to cut off the corners as that cage has rounded corners so shelves don’t fit properly unless you cut off the corners).