Knowing the dangers involved in the quest I was about to embark upon, I made security paramount in the design of my newest facility. Even in deciding to try this again I had to overcome great anxiety and at every stage of procurement and construction, faced new fears. If there is ever one endeavor in my life that I have pursued relentlessly for the love of the perfection of its art, it is the cultivation of this plant. With that, I have overcome.
The problem that plagued me throughout my early attempts at growing, living in a tropical climate, was heat. What to do with all that heat from the lights and an A/C system that struggled to cool that crappy little house to begin with. I ended up with all sorts of designs in various attempts to solve this issue, but always the heat would win.
Initially, I had this idea that I could build a growbox out of a commercial grade freezer that came into my possession. But the thing turned out to be a piece of crap and I canned the idea pretty quickly. After a lengthy design period I came up with a design for a cabinet having a veg and a flower chamber, 2'Wx2'Dx5'H each, that would use two HID fixtures and a dual ventilation system for the fixtures and the grow chamber. The inside of the box is painted in a brilliantly white and durable roof paint that resembles pudding in its wet state. The first issue I ran into was that the cooltubes and the ducting I wanted to use wouldn't fit in the box which had already been maximized for the space. So, I canned the cooltubes and went with open reflectors, figuring that I could increase the ventilation system capacity to compensate.
The ventilation system consists of a two speed 428/293cfm, high static pressure, squirrel cage type blower fan housed in a double walled custom air handler box that has 3/4 inch of playsand filling the space between the two walls. The fan pulls air from the room through the box and then exhausts it into the attic. I was hoping that I had overcompensated enough to accommodate for whatever heat the fixtures would put out.
The fixtures I went with were two Lumatek 240V 400W digital ballasts. After I brought power to the space to run the two units, I plugged them in to see what they would do. Light, glorious, bright, HOT, flippin' light is what they did. Never have I worked with so much light and so much heat before. I almost instantly knew I was screwed by the heat issue again. But I sallied forth with my plan, as the box was already built and there wasn't much else to be done about it.
(Fast forward to the heat trials) The lights are installed, the ventilation system is running, the doors are on, the thermometers are thermomitoring. Ambient temp outside the box is 78F, veg (MH) comes to ~93F and flower (HPS) comes to ~98F. Oh, sh*t. I climbed in, just to see what it felt like. Growing up in a tropical climate, spending summers at the beach and getting into cars after skipping barefoot across 9000deg pavement makes it feel mild in comparison when you have cool air circulating past you and temps are only in the nineties with low relative humidity. Unfortunately, the plants aren't as hardy as I.
I realized that I needed to create at least the mock sensation of having a vented fixture, reflect some of that IR away from the usable growing space and try to salvage my design. I had a local glass shop cut two "shelves" for me that would separate the fixture from the rest of the grow space and installed them just under the fixtures. I left a gap all around the edge of the glass and the interior walls of the box for air to pick up the heat and carry it out. The air comes into the box from filtered openings on the sides of the box and then into light traps before entering at the bottom outer sides of the inside of the box. It comes in the bottom and goes out the top.
This helped a little bit, but not enough. I found this stuff called Energy Film that is transparent but blocks thermal energy in the form of IR and UV light (I know what you're thinking but if you don't see it yet, I'll tell you soon). Great, wonderful, here's my answer. Initial tests showed that the temps were reduced by 10F (veg) and 15F (flower), respectively. This is great because the seeds I started a while ago have outgrown the dual T8 fixture they've been sitting under on my work bench. I continue to let both lights run to see what prolonged exposure will do to the film. The film on the veg side is still functioning fine, but the glass on the flower side shattered under the thermal load. Luckily nothing was in there when it happened. I called another glass shop and had two new tempered "shelves" made and tried again. No shattering, but as I'll explain, it doesn't matter.
This next part requires me to take a few steps back and describe how I got to this point with the plants. I knew it would be a bad idea to experience my learning curve with storebought genetics, so I secured some bagseed and started the germination process. I could tell you some of the stupid sh*t I did here, but I don't think it's as important as the rest so I'm going to start post-germ.
Six little lovelies I had in little (2.5") clay pots. They grew pretty well to begin with, though spindly. Then they started to die. The forums had me repot them (duh!) into 8" pots using a good, natural (no more MG) mix with lots of aeration amendments. They did better for a while but went back to a sickly zombie state of losing leaves of yellow and brown blotches. I still really have no idea what's wrong with them other than it could be some sort of pH issue, though the runoff pH's just fine. Anyway I found one male (Arthur), who ironically performed the best out of all, and placed him into flower alone to harvest pollen since he had such nice genes. When his load was spent, I clipped and dried him and had a funeral pyre in the back yard. He was a good boy (no I didn't try to smoke him, though I thought about it).
From the girls I took two cuttings each before throwing them into flower and left their fate in the hands of the gods. The cuttings, I dipped in Olivia's rooting gel and placed them in soaked rockwool plugs in a heated humidity dome. I did not pH the rockwool plugs as I should have. I should have taken smaller cuttings as it seems the smaller ones rooted more easily. I will still use rockwool in the future but I have an idea for a micro-DWC for clones that I want to try. One of the main things that I have learned about cloning is that oxygenated water is paramount to successful rooting. After the humidity dome staggered along for a while and roots threatened to never form, three finally showed roots convincingly enough to attempt putting them in the primary hydro setup. One died and the other six were jammed into a clear glass beer bottle filled with a mild nute solution and an airstone and left under my bench fluoro. Just take a guess at who started blasting roots almost immediately.
The res is a dark blue 10gal rubbermaid tub that just fits in the growbox. I didn't know that there was such a thing as plastic bin primer so I did it the hard way and scored the surfaces of the tub and painted them first with two coats of flat black paint and then two coats of the same white paint that I used on the grow box. It works pretty well. I even gave a coat of black to to the inside of the lid for good measure (remember this detail). Instead of buying net pots I fashioned my own out of 2"pvc, hose clamps and that web material used to keep rugs and floor mats from sliding on hard floors. These I filled with rinsed hydroton and topped with my rooted clone in rockwool and slid the whole assembly into cutouts in the lid of the DWC. Originally I had planned on using a Burp and Gurgle setup but decided that all that tubing work was going to suck to put together.
Okay, my eyes are starting to cross. I'll pick this up again soon.
Later,
MPB
