lol does sound weird but i couldnt help you out there myself lol, im still finding something that would drain the water from proventing me changing the tank once a week, i was thinking paper kat litter with a layer of fibreglass fly screen then your substrate of some sort. there for the substrate wont go through and mix with the kat litter and change the cat litter once a month or something and should stop from deceases and stuff like that.

coco peat holds water to without releasing any bacteria but havnt tried it yet and i dont know for how long as that stuff likes to be moist all the time