Desiccant Silica for humidity control??

So I have a lung room with a veg cab and a flower cab. The lung room has a wall AC and a baseboard heater, the room pretty much stays between 69-78 F. 69-70 lights out, 75-78 lights on. The veg cab and flower cab each have dedicated air exchange fans. The veg cab exhausts back into the lung room, the flower room to outside via a filter. The RH in the lung room never drops much below 60%, this is good for the veg cab, but too humid for the girls in flower.

So that is the basics. I want to drop the humidity in my flower cab alone. I was thinking of attaching a can to the intake of the flower room, and putting a mesh bag full of desiccant silica beads in the can so as the air is drawn through the passive intake it is stripped of it's moisture content.

Anyone ever have a setup like this? If so, did/does it work? Any thoughts or opinions, things to think of before i spend the $50 or so to experiment?

Even if it does work desiccant is a temporary solution to a continuing problem.

- Jiji

Well, when the silica beads turn from blue to pink I would change them out, put fresh beads in the can and the "wet" beads in the oven to dry, then store the dried beads till the next change.

Dehumidifiers require water collectors to be drained, rendering them temporarily useful.

Thanks for tour thoughts jiji.

Anyone have any experience with this? I got the thought from looking at the dryer on the air line to the compressor at the cabinet shop.

Joven Agricultor said:

Dehumidifiers require water collectors to be drained, rendering them temporarily useful.

Click to expand...

It may not be all that cheap but a dehumidifier with a digital humidistat and condensate pump is where its at.

- Jiji

The air gets exchanged in the flower room every 1 minute. 150cubic feet, I don't see a residential dehumidifier keeping up with that. I'd like to scrub it on the way in. Money is not the issue, spending money on something that is not going to work is. I thought about making an intake "chamber" and placing the dehumidifier in there. I still don't think it'd keep up. $2k on a commercial inline unit is not going to happen yet.

So I was hoping maybe someone would chime in who has experience with an alternative to dehumidifiers, a more direct in line scrubbing route would you.

Whats the RH and temp of your intake air?

The alternative to dehumidifiers is air exchange (from a dry source) and temperature.

Think about how much water the desiccant could possibly hold. Not much.

- Jiji

Also, I think the issue that should be addressed is the actual lung room.

The only reason it makes sense to use one to me, is if your sharing the exact same environments while localizing equipment.

Just my opinion. I’m sure someone will chime in saying desiccant is the shit, it works for me.

- Jiji

The air exchange is from the lung room. Which the temps are controlled via a wall ac and an electric baseboard heater. So my intake air is a constant 69-72 degrees. The lights produce more heat in the veg and flower cab during lights on +5-7F.

The RH of the intake air is normally 50-60%, this is good for the veg cab, so I don't want to lower the RH in the whole lung room, just the flower room, or air entering it. The air exchange is quick so I think I would be better off removing moisture from the air on the way in, than trying to dehumidify the cabinet. Air would simply flow right past the dehumidifier.

Follow me?......
Without the lung room I was fucked, bringing in whatever air mother nature decided to deliver for the day. Lights are closed loop system intake from outside, through the sealed lights and dumps back outside.

I guess this is an issue I'm going to have to spend a lot of thought and time to figure out. Within the next few runs I'd like to add CO2, and I still have to research on that, i may want higher humidity then. This issue is going to take a while to iron out, in the mean time I'm halfway through flowering and don'r want mold, so I have to do something for now. Right now i just have the plants dancing around with some fans to try to prevent mold or mildew.

I've used similar chemicals to control RH.. Its not that great really.. Calcium Chloride is what I used.

When you reach the saturation point of the chemical the performance drops off very quickly.

IF you have to treat the dessicant each time to dry it, its energy wasted. What is the dry time for silica beads?.
IF you gotta fire up an oven that uses thousands of watts to create heat... .. yeah...

I'd like to point out that Dehuey's can be modified to run perpetually.. You could modify the collection container to dump into plants or the water tank for hydroponics.

I was a doubter of the smaller peliter style dehuey but they work... And I'm sure multiple units could be used for small grow rooms.