1. This thing is going to be very hard to weigh down. It is likely to need three ballast pods, each twice the depth of the ones Hambase Alpha uses so I can pack in 4 lead block weights per pod. That's 60lbs total.
2. This hobby stays affordable only when the habitats are small. Cost increases non-linearly with habitat interior volume mostly due to the cost of lead. The current habitat is likely to be the largest single module I ever build. I'm also gonna need help buying the ballast pods and block weights in particular. If you're on the fence about funding this weird shit, now's the time.
3. It will not fit in the aquarium. I mean, if I saw away all the acrylic around the top I can get it in there but the roof of the thing will be just inches from the water's surface. Really not much point then. I will need to find either a very clear natural body of water to deploy this into, with access to grid power nearby or get one of those big partially inflatable above ground pools to stick it in.
Bonus render of Ham colony to the right. The running saucer will fit on the top floor, I think. If not, it'll go on floor 2 and the top floor will have a sort of crescent cut out of it to accommodate the tallest part of the saucer. The black thing on the bottom floor is the heater pad. Oversized water bottle because this thing will eventually be intended for very long submersions, at depths up to 8 feet. If hamsters could coexist (they can't) I'd rate this for between 6 and 10 of 'em. Mice would do a lot better in those numbers.