The propensity of water to hold 02 in solution decreases with increase in temperature.

Metabolic processes occur at a higher rate @ warmer temps.

Yer lookin' for a compromise between divergant growth factors- the best ratio of temp/02sat that you can achieve.

In the practical world, that usually works out to a desired rootzone temp of about 65-75, but you can go higher if you can get the O2sat level up- I've been as high as 13mg/l @ desired root zone temp of 83F, and growth rates were just stupid-well beyond what could be expected a rTemp 70F.

Please do not take that as meaning " Bleed in extra tank oxygen use a water heater and yer plants will get huge". This was an evolved strategy intended to max out a weird ( truely, unimaginably weird) system.

I'm just saying this isn't cut and dried, and there's room to play in here...

But 70F is a good # to shoot for, knowing that you'll need to really think about aeration if you get too much higher...
rhizome Reviewed by rhizome on . Quick Question What should be the Temp. of the water in your hydro water? If I can get a quick response that would be very appreciated. Rating: 5