Thanks man, appreciate it.

The roots can never reach the water by the way. The root chambre and the water reservoir are devided by a wall. The floor in the rootchambre drains into the reservoir at it's lowest point.
I've seen people using ice also and I will as well but that will be a way to get temps down if they are way too high as it is such a temporary fix. I'll modify my growroom or my system until I have a stable solution concerning that.
The waterpump is anchored to the floor of the reservoir chambre so it can never move. It is pressed down by the solid pipes.

I read quite a lot of Amazon logs and most of the guys have only actually changed the water once, when they shift to 12/12 or one time in the middle of bloom. I was thinking every 2-3 weeks or if I get into trouble.

No light leaks by the way, I held up the lid with the plants in it to the HPS and cant see a beam of light get through anywhere.

So far so good.