Underground Water cistern grow room


Yup have the fan going 24 7. Yea I have a feeling that it’s going to be very humid down there in the summer. The 4 in carbon scrubber with duct fan seems to pull it out fast tho. So who knows maybe I’ll get lucky


Love it would be my line of thinking too or boxing intake and exaust to warm intake air and blend with fresh restricting how much actually escapes exhaust.

as a rule anytime you can add more light you are winning most are limited in how much and what kind by temps they generate which makes cooling required. I grow in a shed which uses lighting almost exclusively for heating exhaust is recycled into an adjacent space blended with fresh air then pulled back through space. Sounds easy but I also have outside temps which are about -2f atm so yes heating with lights definitely works during summer I pull cool air from under shed and direct exhaust out


A reostat or simple $10 dimmer switch can be added to fan cord to adjust it’s speed concrete could be covered with styro insulation but will breathe better without helping keep more consistant humidity. Keep in mind you can force plants to adapt to lower humidity it just effects growth rates some but what’s an extra few weeks compaired to failed grow or bud rot


@Donaldj both fans have adjustable speed so I’ve been debating about buying a massive light timer this model to be exact. It’s says it’s for hid hps lighting but wouldn’t it still work great for led. SY400


I expect it would I am cheap by nature so tend to use household digital timer 2 reasons first battery backup so if power goes out it saves it’s settings dial ones only work with power on so an hour outage can mess with my settings. Secondly I would rather spend the money on good meters or better lighting than a timer also I run 3 light rotation so 3 different schedules a multi light light timer isn’t worth it to me. I have 4 $15 dollar ones each of which is a power bar with built in surge protector so if something goes wrong only the lights on said timer turn off.


If you plan on running 6-8 lights on same schedule it’s perfect but they are very comercial in design and meant for larger grows higher power than you’ll every want in a cistern



any idea on this leaf curl I water twice a day unless soil seems wet yet but its 75 to 80 down there and 40 for the humidity. I raised the light up about a inch. I’m doing 18 hours on right now. And only one has the curl.


Looks fine. Maybe slightly over watering. Try misting the soil top instead of watering. They only need moisture right now. Be sure you avoid getting water on the leaves.


Thank you I thought I read something about spraying them once in awhile so that might very well be it. The other ones are looking great so far.

think maybe transplant this coming week


Looks like you’re using coco? If so, you will need to water daily most likely if your space is only 40% humidity. What are you planning to transplant into?


It’s grow germination soil i got from a ace hardware.ive been debating that. I have fabric pots on the way and was looking at fox farm soils. But seems expensive. I also already have the three fox farm nutrients. Any advice on some stuff I could pick up locally


Happy Frog is all I use. 5 gallon fabric smart pots? That’s what I use as well. If the pots aren’t there by Monday, you may need a temporary home. Once you get that first set of true leaves, they take off!


Ace hardware has free ship to store pickup and they carry a good variety of potting soil. You might want to check out the main website. I’m pretty sure that the Black Gold line is pretty good plus they carry a few other brands. Hope this helps you :grimacing:


Well guys been hard at it this morning. I was only using about alil less then half the cistern to grow. Then I thought this was a waste of space so I remodeled a bit and gained so much more room. And gained a separate smaller room to attempt to try to clone.


@Iowacountryboy hey, do you have speed controllers for the intake and exhaust fans? They may help to maintain the Temps and Humidity if you can control the amount of air actually coming in and leaving the room.


@Dwayne yes both have speed controllers. The problem I was having is that with both running on low it was getting to cold and losing almost all humidity. So what I’m in the process of doing is making a large box to put a heater in then have my fresh air run into that with a fan pulling from the box to mix the two so it’s not so cold. Hopefully it all works out


one more light coming but transplant complete


Well electric has become an issue over loading and tripping the gfi. Would a surge protector stop this.or am I just pushing the 4 outlets to begin with


Sound like your over loading the circuit to me
I would get a anp reading on the breaker
It’s possible you have a weak gfi also
Is it a gfi breaker ir outlet @Iowacountryboy


@Countryboyjvd1971 I’m almost 100 %I’m over loading it.