CO2 in a hydrohut

I've got a hydrohut original that I'm using for the first time. I only started it a few days ago and I'm still getting everything dialed in. I want to setup a bottled co2 system. I already have a hydrofarm unit with regulator etc. and I'm going to go get a tank tomorrow. My questions are around how I should setup my system to trigger the CO2.

First, I have a fresca sol water cooled light with a 1000w sodium in it. This keeps the temps in the hut at MAX 94 degrees at the plant tops after being on for 12 hours with NO ventilation. It's also very warm in my area and as the weather gets colder this will chill even more as it's in a uninsulated basement. I have a 123 CFM Can-Fan with a carbon filter that will keep the hut at sub-80's temps if I leave it on all the time. Right now I have the fan on a attic fan thermostat that keeps the temp range around 79-84 with the setting I use now. It cycles every 10-15 minutes I would say and runs for just a minute or two to cool everything back down. Also the hydrohut isn't perfectly sealed but fairly close. There are some vent flaps that don't stay totally shut but I could probably tape them if I needed to.

I want to have the best growth possible of course, so how should I setup my CO2/fan system? I'm thinking of a system like this:

1) Attic thermostat turns on fan once temp inside reaches X temp (already have this)
2) Any time the fan isn't running CO2 injection is happening. Once I looked at the CO2 sticky in Indoor Growing I realized I could bring the room up to 1500 ppm in just 5.76 minutes with the CO2 equipment I have.

So, should I be injecting CO2 at a high rate for the 6 minutes then holding the fan off till it gets to a very high temp, only to refill it again after the fan stops running. I'm not sure how long I could push this cycle to if I let the temp get fairly high.

Or should I keep the temp low and just slowly inject CO2?

I already have a CO2 system that will do .2 - 2 CFH. Now I'm just trying to figure out how to wire it up. I have a relay and I'm going to solder it up so that when the fan is running it will cut power to the CO2 system.

Any advice on how to use it most effectively?


Thanks!

I ran into the same problems that your going through when I got my CO2 system.
There are systems out there that will automatically turn your CO2 on/off when PPM levels reach a certain point. I looked into those systems and was sticker shocked.
I thought to myself all I need is something that I can put in the room that will monitor how much CO2 I have in my rooms.
So I bought this CO2 monitor instead.

It's made by Senselife. I only paid $180 for it. It's still a hell of alot less expensive than a CO2 delivering system, which goes for about $600
Well I set up my CO2 lines to be inches away from the tops of my plants.
I also set up the regulator to be turned on during light hours with a timer set in intervals of 15 minutes.
The CO2 monitor is placed in the room a bit lower than my CO2 lines.
I keep my intake blowers, my exhaust blowers, and my oscillating fan on at all times. The oscillating fan and the CO2 regulator are the only things that turns off completely when the night hours begin.
But basically everything stays the same when the CO2 turns on.
The Senselife monitor will show PPM readings from 200 - 3000.
I keep the CO2 regulator set at somewhere in between 3-5 and the PSI set at 30.
I had to mess around with CO2 regulator for awhile until I had the right setting. But once I had the right setting. My PPM levels once the CO2 was turned on are at 1300 - 1500. Once the CO2 turns off the CO2 clears out of the room in just a matter of a couple of minutes, and my PPM levels drop down to about 500-700.
I'm glad I did alot of research on this before I bought anything. This Senselife monitor works very well with my set up.
I go through a tank of CO2 about every 2 weeks.

Hope this helps you out.

That will help but you are wasting the co2. Can you change it to a sealed room? Yon can run your cooled lights and then seal the room. Run an a/c system for the room itself that will help maintain the temp where you want it. Then you only need to add co2 when the ppm drops to a certain point. You can vent the entire room with your current fan twice a day just to freshen up the room a bit so to speak. Remember the plants use co2 so thats all you are really concerned about other than the air temp..

I realized last night as I sat and stared at my setup while smoking a doob that while I'm containing the heat in the water with the water cooled light, I'm not releasing it in any way. I stuck my hand in the water in the barrel and feeling that it was almost too hot to touch, I realized that I need a radiator to dump the excess heat into the air, outside the room. I'm going to go to the car parts store today and see if I can find a cheap heater core from a car to use.

I think if I do this I will be able to get the temp in the room down ever further and have to vent much less often. My other idea was to build a small encosure to house a window AC. I would seperate the box with a cooling side and an exhaust side and circulate outside air through the exhaust side and cool air to the room. This seems like and extreme measure to me though so I'll see how far I can get with the water cooling first. Wish I had a pool to circulate the water in!

dosent the hydrofarm unit come with a timer that triggers the co2 feed?

Ridgegoo said:

I realized last night as I sat and stared at my setup while smoking a doob

Click to expand...

That's funny....
I do that all the time. I'll pull up a chair and sit in front of my grow rooms. I'll get super stoned and think about how I can make it better.

I really should buy a voice recorder and record what I think about. Due to the fact that when I sober up I can only remember fragments of what I was thinking about.

Ok, I went to the parts shop yesterday and found that the cheapest heater core I could find was for a 1980-1990 F150. $30. I put it inline with the water flow on my water cooled light and put a little clip on fan blowing on it. My hydro hut didn't get above 82 degrees all night, but the ventilation never fired off so it got really humid and I'm sure all of the CO2 was gone. (I don't have the co2 running yet since I haven't decided on the logic to use).

Now I'm thinking that having the fans on timers as well just to remove the humidity would be the best. How common is a humidistat? Will they have it at my local hardware store? I'm thinking of this setup now:

Timed co2 release according to the instructions that came with the co2 gear for keeping this size room to 1500ppm.

Exhaust fans and intake fan set to fire if temp > 82 or humidity > 50%

Adding a high powered fan to blow on the heater core to keep the water for the light cooler.


Doesn't having hot water in a container inside the room create humidity?

Ok, couldn't find a humidistat in town so I broke down and brought a controller. I got a used centurion EVC-2 from a guy who works at the hydro shop for $200. I'm going to hook it up tonight and see how it works.

The centurion controller is awesome. So much nicer than the thermostat. I have the following set:

Day Max temp
Night Max temp
Day Max Humidity
Night Max Humidity
temp deadzone settings (how far down to cool it once you hit the max temp)

And it automatically kills the CO2 when the fans come on. It would control an airconditioner and a dehumidifier but I just use a pair of fans in my small setup.