[cypher]

Hi & welcome to the forum
Syrian hamsters will eat about a tablespoon of food a day, to begin with they may need more so they can build up a bit of a hoard.

It's better if your ham can see out of the cage or tank, just filling the base part of the Zoozone up to the clear plastic should be ok.

Tubes should be at least 8cm I think, they do vary a lot in size & a larger ham may need tubes of closer to 10cm.

Hams soon get used to normal household noises so vacuuming is fine, I generally tend to begin by just doing another room close by & not going close to the cage for the first few ays or a week when I bring them home then I'll start in the next room before coming into the room where they are so they get some warning & then after doing that a few times they should be perfectly fine with it & not bothered at all.

Balls are highly controversial so you will possibly get varied opinions & just have to make up your own mine.
I personally don't think they offer any benefit & can be both stressful & dangerous, far better to use a playpen or other safe play area with toys & other things to explore.