For Nimh, I don't think she's getting cleaned out more than once a month - she isn't dirty (except her wheel, which is a smidge grubby) - she smells good, and her megazorb looks pretty much pristine
Every 2 weeks would be insane for cost of substrate, even with megazorb and her current cage - she's got almost half a bag of it in there
As for tunnels, she is currently in a Perfecto, so her batcave is dug out beneath the lowest shelf (the substrate goes up to shelf-height), not really a tunnel, more just entirely hollowed out
That said, I spoke to Rodipet, and they are thinking of doing international shipping in April - I so want their ceramic tunnels and houses. They are hideously expensive, but I'm hoping my partner will give me animal vouchers again this year, then I can buy some for both sets of hams. She does like making her own tunnels though - I have a cardboard tube stuck into the space where her batcave is - she fills it with megazorb and makes her own entrances
But yes, once she's moved over into the Detolf, she won't have the shelf, so I'm thinking Rodipet (or cardboard in the short time in between) might be the option there
Looking forward to the Detolf
No horrible shelves to try to spot-clean under