Jul 18

Help, why is my humidity dropping like a stone when my lights are on during the night and it is ok when lights are off midday to 6pm

Jul 18

What are you using for an inline fan? Is it on 24/7 or only on at certain times? If you're using the AC Infinity with temp/humidity setpoints, then that could be it.

nealross21

Jul 18

Hi, no my inline fan is shit, its's a systemair rvk, its what i got with the package and it is on for 30 off for 15, it has no speed controller. but i have just bought a Phresh Hyperfan V2 - 150mm (560m3/h, that should make a big difference hopefully, i have a 4x4 tent with a 600w m/h for veg.

Mr. Grow It

Jul 19

Got it. Well, unfortunately in that case you probably will continue to have swings in your temp/humidity. Plants do a process called transpiration which is a release of water vapor into the air. That's one factor that adjusts the humidity. Also, after you water your plants you'll notice a spike of humidity as well. Due to that, many growers avoid watering before lights off.

nealross21

Jul 19

Ah ok, will the spikes cause big problems?, nee fan will be fitted next week.

With the new fan are there any pointers to keep the humidity/temp stable?.

I will chamge watering to when the lights are on aswell, thanks 👍

Mr. Grow It

Jul 22

@nealross21 Too large of swings could stress the plant out to the point where it becomes a hermaphrodite. If you get the AC Infinity inline fan, that has a controller so you can put temperature/humidity set points. That greatly helps stablize the conditions in the environment.