Please check me! 10x10 tent in a shed grow room

[mfdoo0mm]

Hi all,

First of all, glad to be apart of the forum! I very much respect all you experienced growers out there, this isn't easy!

I am getting back into growing (but still fairly novice) and had a couple questions regarding my setup. I've attached a sketch for reference. Budget is ~$5,000. Growing in PNW (United States). Background behind problem listed in black, question in red.

Grow Space
So I have an ~10'ftx11'ftx8'ft shed outside. It's constructed of some corrugated tin, brick floor, wood paneling, etc. No insulation exists in the tent. There are three very large single-pane, caulked in windows. The door does not seal and has gaps in the frame. There is 240VAC service, with a sub-panel that reads two interlocked breakers @ 30A each. This makes my limitation ~30A BUT am getting an electrician to check it out & run new cable to up it to 240VAC ~60-65A. Sounds kind-of like a mess, right?

So I decided to put a 10'x10'x~5-6' tent (am double checking dimensions to make sure it can fit). Am going to insulate the shed walls and cover in plastic. Not sure what to do about the door (velcro strips? weather strip? would prefer it to seal)The windows will need to be boarded up and sealed for light, I don't want to assume the tent is 100% light proof, so it will act as a second light barrier point.

Anything I'm not thinking of here?

Lights
(4) 1KW MH (Eye Hortilux Super HPS) (~22A @ 240VAC & 0.8PF)
(4) 1KW HPS (Eye Hortlux Blue) (~22A @ 240VAC & 0.8PF )
(4) SunSystem XXXL Magnum Air-Cooled Hoods
(4) Switchable ballasts
Need some direction on light timer. Will explain more in ventilation.

Ventilation/Climate Control
This one I think I need some direction on.

Intake (TENT,TO BE DUCTED THRU SHED NEAR BOTTOM AND THEN TO TENT) - Can I leave this passive & size it according do the chart listed here?

https://www.icmag.com/gallery/data/500/Intakesizing1.jpg

Exhaust (TENT, TO BE DUCTED THRU TENT AND THEN SHED TO OUTDOORS) - @ 600 ft^3 6" 5 mins/change = 120CFM
Does this sound reasonable? I am reasoning that with the lights being air-cooled, and ambient outdoors around the shed being around 37 degrees - 51 degrees. Maybe I am creating a cold problem?

With the lights being air-cooled and the ambient temperature being low, but with the surrounding shed outside the tent insulated, is there a fan/temperature controller or setup method which involves using some of the heat from my lights to heat the room? At the same time, I'm restricted by 6' clearance @ ceiling, so the lights will probably be pretty close to the plants at some point. Or, should I just get a space heater and have that on a temperature controller instead?
Intake (Lights) - Will be two rows, one for each light. So that means two fans. To blow cool air over my lights, I'm going to take the ft^3 of the ducting and add it to the ft^3 of the lights.

Exhaust (Fan) - Just a hole out the other side, nothing fancy. Do I need to oversize this hole as well, similar to the exhaust in the room?

Is this an adequate ventilation design for the lights?
Dehumidifier
Outside it can get humid, and range from 66% to 99%. I'm thinking on an air-cooled water handler. Pretty neat stuff. If it adds too much complexity, I may just stick with a dehumidifier and suspend it from the ceiling with chains, then figure out a way for it to outflow into a reservoir or something.

Growing!
Growing medium in soil. I was thinking of doing (24) plants, 6/1K light. Been focusing on the construction of the room so much I haven't picked out nutes, soil, etc. Any recommendations?


I think I will add more questions as I think about it more. Hopefully I am not just repeating the million questions posted here by all us newbies Thank you for reading.

 

[Catfish John]

Hello Mfdoom,
I will try and help as much as possible here. As far as the door goes, from he inside of the shed you can tape up panda plastic covering the whole doorway. Then they have zippers that are very easy to apply. All you do is unstick the zipper and place it where you would like the opening to be then cut the plastic between the zipper and boom. Now you can open your door and there is another plastic light proof barrier that can be unzipped giving you access to your shed.

If you decide to stay on the 30 amp circuit you can get a 30 amp sunlight supply timer box (google) they work great and you can plug your 4 lights into the box on a timer. you can also plug in your 2 intake fans into the same box that way they all turn on at the same time. There is a fan controller that is called a tmp-dne by C.A.P. You can plug your fans into this controller and when your room gets to say 79 degrees the controller will turn on the fans to pull cold air across your lights and cool down the room. then once it gets to say 76 it shuts off, You can control the deadband.

I would suggest bringing fresh air in from outside through a Hepa filter or adding co2 into your room. Either will prevent the stagnant air. But it seems you will need the dehumidifier either way since it is so humid where you are. I would definitely suggest reusing your water from the dehuey because it is 0 ppm.

As far as soil and nutes go, everyone will give you different suggestions and many people do great with what they use. I have been getting amazing quality using the K.I.S.S. method which is documented on this site. I personally like coco alot and feel like it allows the plant to grow at a very fast and vigorous rate.

I hope this gives you some good insight but feel free to ask any questions and I will do my best help. Good luck

 

[St. Phatty]

Been focusing on the construction of the room so much I haven't picked out nutes, soil, etc. Any recommendations?
[/COLOR]

A standard baseline for Canna production is Foxfarm Ocean Forest. (which works out real well for Foxfarm.)

Square pots allow you to pack the most soil in a space. Since you have limited space and want to get the most out of it, Square pots seem right. 2 gallon black square are a common size at a lot of grow places.

Some supermarkets sell their deli buckets, and their is a 4 gallon size that is square and super-useful. REALLY pack in the soil, if your plants need it.

If you have $5K budgeted I would buy enough Foxfarm soil to fill whatever pots you use, AND start looking at local alternatives, to see how they perform compared to Foxfarm.

Premium compost where I live is $30 a cubic yard. Foxfarm, when it's on sale, is $10 a bag (1 1/2 cubic feet), which is $180 a cubic yard.

To supplement it, I would add -
* High phosphorus Bat Guano
* Bone Meal
* Agricultural Lime.



Adding a bunch of nutes tends to make the run-off more acidic (= plants not getting food, even though they're surrounded by it.)

So, you need to measure the run-off. I don't know if you have a pH meter.

I have sometimes taken the liquid in a jar, and asked the hydro store guy if I could borrow theirs. That actually works sometimes.

The lime is to help raise the pH. Any of the supplements can be overdone. One tablespoon to 1 ounce per gallon of soil is a decent starting place.

 

[Granger2]

I'm really concerned about the door. It not only needs to be light and air proof, it needs to be critter proof. You'll have rats in there in no time. They will be a recurring problem. They are seriously damaging. They are attracted to electric wires, and will gnaw on them. They shit and piss on everything. They'll quickly and easily gnaw right thru your tent. You will not enjoy going into your room and discovering that you're in there with rats. You also won't enjoy being on guard all the time in case there might be rats behind evey pot and other items. There will also be possums, coons, etc. at times. All these will fuck up your crops. You will need, IMNSHO, to remedy this before you can do anything else. It takes metal or wood to stop them. I've seen where they gnawed thru 2x4's.

You also have a brick floor. This will allow insects into your room with impunity. I would suggest using rubber pond liner, SEALED with Gorilla tape, over the brick. This material is like what an inner tube is made of and can be patched simply the same way as an inner tube. Go to the bicycle shop for a cheap kit, although I haven't needed to patch mine in 10 years of use.

I don't think a 10x10 tent will fit. I'd save my money and go without a tent. You can frame, insulate, and put either plywood or drywall over it. You can do it right over the windows. I would go with a sealed room with AC, dehum, and CO2. Unsealed, you'll have to deal with high humidity all the time with the associated PM and Botritus. In the PNW, just not worth the frustration of dealing with fungi that fuck up your crop, require mitigation with fungicides which you will smoke. Get set up right in the beginning so you don't have these problems while you've got crops going. Good luck. -granger

 

[mfdoo0mm]

Thank you all so much for your replies!

We are scrapping the tent idea. After we took measurements again, it is kind-of a weird trapezoid shape. I've attached a picture for reference. We will be going in the direction of framing, insulation, and plyboard-ing along the walls.

Hello Mfdoom,
I will try and help as much as possible here. As far as the door goes, from he inside of the shed you can tape up panda plastic covering the whole doorway. Then they have zippers that are very easy to apply. All you do is unstick the zipper and place it where you would like the opening to be then cut the plastic between the zipper and boom. Now you can open your door and there is another plastic light proof barrier that can be unzipped giving you access to your shed.

Hi Catfish John! We are going to be pulling our own ~60-65A cable and terminating it. The existing load center installed currently @ the shed supports up to 70A, so we'll be swapping the breakers out, etc.

Now, your comment seems to be conflicted by Granger2, who is adamant about us re-framing it. I think we will go in the direction of doing an adequate re-framing job and getting a solid permanent door in there. But this is great advice, thank you

Now, I don't know about investing in co2 this early. Seems like it will make things more complex (read: easy to fuck up) too early in the game for us while we're still learning. Could I supplement with an intake fan instead? Or, is the passive intake good enough (granted that there will be negative pressure buildup from the room exhaust fan)?

A standard baseline for Canna production is Foxfarm Ocean Forest. (which works out real well for Foxfarm.)

Square pots allow you to pack the most soil in a space. Since you have limited space and want to get the most out of it, Square pots seem right. 2 gallon black square are a common size at a lot of grow places.....

Square buckets are a great idea! One of those moments, "Why didn't I think of that before?!" Thanks man!

Although I like the idea of organic soil, again I am worried it will make things too complicated too early. I am afraid to introduce pests into the garden via the organic soil.

I will be purchasing a pH meter and probably all meters/gizmos I need for testing and logging. I am a bit of a science nerd, so I am very much looking forward to the logging the data part!!! Thanks so much for your other tips, I will keep them in my hat of tricks until I need them .

I'm really concerned about the door. It not only needs to be light and air proof, it needs to be critter proof. You'll have rats in there in no time. They will be a recurring problem. They are seriously damaging. They are attracted to electric wires, and will gnaw on them. They shit and piss on everything. They'll quickly and easily gnaw right thru your tent. You will not enjoy going into your room and discovering that you're in there with rats. You also won't enjoy being on guard all the time in case there might be rats behind evey pot and other items. There will also be possums, coons, etc. at times. All these will fuck up your crops. You will need, IMNSHO, to remedy this before you can do anything else. It takes metal or wood to stop them. I've seen where they gnawed thru 2x4's.

You also have a brick floor. This will allow insects into your room with impunity. I would suggest using rubber pond liner, SEALED with Gorilla tape, over the brick. This material is like what an inner tube is made of and can be patched simply the same way as an inner tube. Go to the bicycle shop for a cheap kit, although I haven't needed to patch mine in 10 years of use.

I don't think a 10x10 tent will fit. I'd save my money and go without a tent. You can frame, insulate, and put either plywood or drywall over it. You can do it right over the windows. I would go with a sealed room with AC, dehum, and CO2. Unsealed, you'll have to deal with high humidity all the time with the associated PM and Botritus. In the PNW, just not worth the frustration of dealing with fungi that fuck up your crop, require mitigation with fungicides which you will smoke. Get set up right in the beginning so you don't have these problems while you've got crops going. Good luck. -granger

I agree with you about the door. We are going to look into reframing and putting something different in there. Never done it before, but I can learn! We are also abandoning the tent idea (see above), and will be doing as you describe.

If I seal/caulk off where the floor meets the wall in kind-of a trim, could I eliminate the potential for pests to get in? My plan is to basically caulk/foam filler everything that isn't going to become the opening for a duct.

I always get confused on the "sealed" room. I imagine that it's like a lab/clean room type of setup. But there's no way people are actually "sealing" the room on regular budgets. Do you just mean sealing off all the open points (like im describing) and not intaking any outside air, but rather injecting co2? I love this idea for a future grow, but like I mentioned previously, I think it will make things too complicated in an already somewhat complicated grow! We can always buy a co2 setup later (if my understanding of "sealed room" is correct) and board up the intake/exhaust ports.


Thanks again everyone!

 

[aridbud]

Can you construct a fake wall in your shed, accessible door? Did that to an insulated garage once....appeared to be an indoor tool shed closet (6 ft. deep, 8 ft wide, 10 ft tall)....instead a great growing space! Had to bring in water, but only grew 8 plants.

Good luck with your plan!

 

[Granger2]

mfd,
Your ideas about what a sealed room is are correct.
Really man, CO2 ain't no thang. Check these:
http://www.hydrofarm.com/resources//co2calc.php
http://growershouse.com/co2-calculator-for-grow-rooms

And the amount you use doesn't have to be exact or optimal. Just enough to keep it above 400 ppm. This is easy and cheap. I carry my tank from house to car in a suitcase w/casters so the neighbors don't notice. Keeping it at 400+ppm doesn't require frequent refills. Running an AC just to keep temps tamed to below 80F doesn't cost that much, especially in winter. It will cost FAR less than growing a crop for months with big nice buds that get ruined by Bud Rot [Botritus] in the last 2 weeks. In the PNW, if you are not sealed you'll almost certainly get Bud Rot. Bud Rot means crop loss.

I would do your framing, insulating, plywooding. Then I would lay the pond liner with a few double sided tape strips, and run it about 6" up the wall, and Gorilla Tape it to the wall. This will keep bugs out, and pond liner doesn't cost that much. When you step on brick, they move slightly and Caulking or foam sealing will break loose and bugs will be able to enter. Covering it will be something you'll be glad you did.

BTW, check out fabric pots.

 

[Catfish John]

Hey Mf,
I would go with Grangers Ideas, he is much more experienced and offered up lots of very good points I over looked! Have fun!

 

[Bmac1]

Ill throw another suggestion in the box. Save money on the reflectors and just hang bare bulbs and run 4 donuts.

 

[mfdoo0mm]

For everyone who helped me, thanks!