Just a tip on your heating idea

I am an LED grower and my light runs completely cool. What I do for heat is incorporate 4 x 20w CFL. The nights can be quite cool so I have the lights come on at night to compensate.

I just find it a better idea to heat with light where you can. Perhaps if your days are cold as well as your nights heaters might be your best solution.

But definitely think of heating with light if you can manage it

Take care !