More flexwatt questions

Can I just have my tub sitting on the flexwatt or does there need to be a little bit of space between it?

I am going to have it on a melamine shelf. I will take a pick of my shelf and stuff later. I need to clear it off.

It can just sit on it.

Yup. It can just sit directly on the flexwatt. That's how I have it and haven't had any problems yet.