Grow Room Calcium chloride dehumidifiers?

[Highstreet]

Hey guys my humidity has been quiet hi around the 70% at abot 21degrees c in my tent at floor level. Ide like the humidity to come down a bit in last few weeks.
Will these calcium chloride tubs help dehumidify my grow tent or will it be pointless cause its always refreshing the air with extraction.
Has any one used these ?

 

[LabRat]

Those are not going to work at all. They are for absorbing moisture in an enclosed space that doesn't get fresh, moist air added on a regular basis. Something like a parked motor home or car that isn't being used for some time to prevent mildew but useless for grow rooms.

What you need is a real dehumidifier but not sitting in your tent or it's damn near useless too. Either use it to dry the air in the room that your tent pulls air in from or rig some way to feed the air thru the dehuey and into the tent so it comes in dry. I'd recommend getting a temp/rh controller for your exhaust fan too so it's not running all the time unless your temp and/or rh is high enough all the time to make the exhaust fan run continuously.

A bonus with the dehuey is you can collect distilled water from it and give it to your plants. I only use distilled or RO water to feed mine.

 

[Highstreet]

Agg I thought as much. Im in SA at the coast so its hot and humid. I run the extractor 24/7 and the circulating fan in the tent.
Was thinking now if I run the ducting down to the pot level will it suck the cold dense air out better and leave the hot dryer air at the top side of the tent perhaps?
If I dont come right ill order dehumidifier. Was looking at those peltier units.

Also I run the lights at night my foto flower tent is on 5pm to 5am and other tent on 18 is from 3pm to 11am.
I do this to keep temps down but would it make any differance with humidity running day or night lights?
Flip I have a feeling its like trying to sweep sand of the beach.

 

[LabRat]

If you have a fan in your grow areas to circulate the air like you should have then the air should be the same temp from top to bottom so moving the ducting around won't really do anything.

Ideally what you want is to run a sealed room so you can use a dual hose AC unit or a mini-split to reduce your humidity to where you want it and keep temps and the whole environment dialed in just right. That's been my plan for a few years now but just haven't got around to it yet.

I live way up in northern Alberta and I usually have problems with the air being way too dry but we've had a wet spring/early summer this year so the rh in my grow room is running 75%. Not a big deal as I'm only vegging plants in there right now and it should get lower as the weather gets back to normal. Messing with my outdoor plants too with all this rain.

Having lights off during the warmest part of the day is a good idea but it's not really going to help with the humidity. RH always goes up when the temp drops but that doesn't mean there is more water in the air just that it's is now higher due to the Relative Humidity percentage in relation to the temp. Still not good when the plants are in later flower and can cause bud rot if too high.

 

[bad dragon bzzz]

yep they for caravans/sheds or a dank cupboard.
if the rh % and or temps is much different top/middle/bottom of tent.then get another circulation fan.
goofd luck n keep er lit

 

[elcoloan]

Hey guys my humidity has been quiet hi around the 70% at abot 21degrees c in my tent at floor level. Ide like the humidity to come down a bit in last few weeks.
Will these calcium chloride tubs help dehumidify my grow tent or will it be pointless cause its always refreshing the air with extraction.
Has any one used these ?

I use them in my 2x2. They are not pointless, they do work, but not as well as an electric dehumidifier, and to get any significant decrease in RH, you need to place several of them in the tent. I put them in the tent, next to the place where fresh air comes into the tent, and if I can I put a fan in front of them with the back of the fan toward the tub (that way the air that is sucked in by the fan is passed first through the tub). I can buy the calcium chloride salts in big bags really cheap and just refill those tubs. I do need to refill the tubs about every week. Depending on how i set the tubs, I can lower RH by 10-15%, never been able to lower more than that though.
With all this said, I would nevertheless recommend an electric dehumidifier.