Search DWC Club and see my system .

I keep my res . at 70 w/ lights off , but it ends up higher 72 / 76 when lights are on , 2000w heats it up a lil .

You've got the right idea w/ a pump to chg out nutes , unless your running a bigger system theres easier ways of going about it = you'll see in the thread I mentioned .

You'r ebb n flow sys. will be easy to control water temps = a submersible fishtank heater . It's ambient room temps I have a lil more trouble with = I'm in the north too . I've read it's best to keep lights on / off temps within 10 deg. of each other . If the spot gets down to 55 you might need a heater for the room / spot . I try to keep my low temp around 65 . High at 75-78 . It doesn't always happen though .

Peace
Crispi :stoned: