BTW; there is more oxygen in an outside room and it would be cooler air too, this effects the amount of DO. If you could take cold air from winter outdoor areas or a refridgerated space it would increase the DO level siignificantly. (Cold air is denser and will help lower the water temperature increasing the amount dissolved)
The grower comparisons aren't really valid as each room has many many factors that are in flux and are different sizes, plant numbers and sizes, light values, nutrients used, ambient temps and humidities and so on. Peace Bad...
The reason I do this, I should have pointed out, has nothing to do with DO in nute solutions...it is because of studies, controlled studies done where it was shown that O2 infused media produced consistently higher weight dry mass (minus roots) in Hydroponics than just an aerated reservoir. Im just covering my bases, got plenty of extra air and 5 cents worth or microtubing, yeah makes me feel better for sure. Until i can get a brix meter and a DO meter then i can experiment my little ass off...
I try to keep my room around 76-78. On hot days it will go a little above 80. But my res temps are always about 10 degrees cooler then the room itself.
Plants have to work harder to stay cool if your temps are up and RH isnt there with it, which means more water uptake and evaporation. You can go up to 90+ degrees with a Co2 enriched environment, but I would suggest letting your temps get that high, unless you want fluffy, airy buds.
I like to run my room a little cooler. In a range that I would be comfortable at. Then enrich it in Co2 and maybe raise the temps just slightly by a few degrees.
If you keep your room at 80 degrees, then hit them with 67-73 degree water, the plants done seem to like that much. I look at it as it being a hot day outside, then someone throws a bucket of ice water on you. You'll go into an initial shock, then get use to it. So I try not to let me res temps drift too much away from what the room temperature is.
Right on...thanks for that, I am going to start keeping them lower tonight, kinda funny that gut feelings are usually right about growing this stuff...
I keep my RH up on purpose. I read a thread on here and found some studies done on a thing called Vapor Pressure Deficit. My take on it was exactly what you pointed out, in essence wasted energy by the plant that should be directed into photosynthesis. I feel that anything that optimizes P'synthesis is what needs to be focused on.
When I first used CO2 in a tent and I could not keep my humidity down and everyone told me I was screwed. That is when i found a thread on here about VPD and then found more stuff online. That grow ended up being great. The only thing to be careful about is bud mold, but someone, I think Seamaiden told me to keep good air circulation and keep your plants clean it should not be a problem, and it never has been for me, but i do live in a very dry mountain climate.
How do you keep your res temps that much cooler than ambient if you dont mind me asking? I am lucky enough that I have the room in my new place to have the res' outside the grow room. I am always open for info though cause I might need it oneday, so I would like to know if you have like a big res or what?
I read on here that some peeps are cutting a 4" hole in res top and installing a pvc fitting and attaching a computer fan to blow on top of nute solution and this would cool it up to 10 degrees cooler. I did a little experiment and propped my res lid up and tilted one of my fans on it and it did cool it down 5 degrees in 10 minutes.
I am going to remember this for the future, but since i agree with you about shocking roots, I am cool with my res temps at 72-74. I know i have good DO with my method as a friend of mine borrowed a DO meter from school several different times and has measured my res DO on several diff occasions...i keep a steady 8ppm in res and in my table (we measured during first flood and after 3 consecutive floods with no appreciable drop). I use 2 12" airstones per res on a Commercial Airpump 5 and puts out 88lt/min. When i was using my chiller, I MOST DEFINITELY observed epinasty (down canoeing of leaves) at 68 degree nute solution. So, given that this is a indication of low DO, I sorta came to the conclusion that just cause the DO is there might not mean that it can be used if the roots are fucking shocked out of their little Rhizo-wits...lol
I know that i people use water that cool and I am sure it works for them, but with my strain of bbc, and my deathstar, it does not.
Anyway im rambling, thanks for the info and the post and in advance if you repost..
peace
shit, guess i should start or add on to another thread, I apologize for jacking the thread people