Thanks for all that information. It makes me a lot more confident about this grow.

Another question about the water though, I finally got my TDS tester today because I wanted to makes sure that my water is ok. Turns out the water out of my fosset is around 800 ppmand filtered water I use around 450 ppm. Are those figures really high? Should I switch to RO water with a little added calcium and magnesium?

I know I'm going to stop drinking my filtered water now.