Low temp with adequate VPD vs High temp no VPD for co2 enriched room.

Okay so I can't get my humidity up to the 60-70% RH with 80+ temps to benefit from the co2 AND vpd. If my room is 80-85 usually I land around 30% humidity at around that temp. I can get my room humidity up to 55% - 60% when the temps are around 73. The higher temp will promote faster growth with the co2 enhancement. The lower temp will move me closer to ideal VPD. Which would you choose?

steveydvee said:

Okay so I can't get my humidity up to the 60-70% RH with 80+ temps to benefit from the co2 AND vpd. If my room is 80-85 usually I land around 30% humidity at around that temp. I can get my room humidity up to 55% - 60% when the temps are around 73. The higher temp will promote faster growth with the co2 enhancement. The lower temp will move me closer to ideal VPD. Which would you choose?

Click to expand...

If you're running HID, I'd aim for 76-78f and f! the vpd.
I'm right around 78f 50RH on, 68f 60RH off with no issues.

LED?
IdK.
(No CO2 enrichment though)

Running HID, I have an undersized AC unit so it literally sucks alllllll the moisture out of the air. The temps start at around 68-70 @ lights on and slowly climbs to 83-85 max towards the end of the light period. The evaporative cooler keeps the humidity at about 40-50% RH @ 70's and 30%ish @ low 80's. Night temps are at 68-70F with 50% humidity(I just leave the evaporative cooler on all night to re-hydrate the room) and to keep the max heat during the day below 85. Does this sound okay?

I'm attempting to chase a better VPD.. last week I didnt have the evaporative cooler and the humidity was 10% at 85. At this point I feel like I'll have to install a misting system of some sort :')

steveydvee said:

Running HID, I have an undersized AC unit so it literally sucks alllllll the moisture out of the air. The temps start at around 68-70 @ lights on and slowly climbs to 83-85 max towards the end of the light period. The evaporative cooler keeps the humidity at about 40-50% RH @ 70's and 30%ish @ low 80's. Night temps are at 68-70F with 50% humidity(I just leave the evaporative cooler on all night to re-hydrate the room) and to keep the max heat during the day below 85. Does this sound okay?

I'm attempting to chase a better VPD.. last week I didnt have the evaporative cooler and the humidity was 10% at 85. At this point I feel like I'll have to install a misting system of some sort :')

Click to expand...

This sets me free to explain HOW to really make gassing work.

You get an environmental controller!
Set the high temp limit to around 81
Set the RH limit to 70

Plug the cooling into the EC unit/exhaust, and walk away.

This will cycle the gas only as needed to hit your gas ppm level setting. (do NOT try 1500 ppm! Indoor growers as a rule, can not supply enough light energy to make that work. A 1K DE HID will give you 1300 ppm effective use. Under that? 1200 is about the real ppm limit. 1000ppm works quite well)

The unit will shut off the gas and turn on the exhaust and cooling and stop at the shut off point. The gas turns back on and the whole thing repeats.
These also shut down the gas and return to cooling and exhaust at "night"

Here's a good read.

My favorite section:
The Night Cycle, Respiration and Oxygen
(Grows need oxygen....sealed rooms must be appropriately vented. "Outside" air is the only souce of fresh oxygen.)