sputnick

i see what you mean about the paint now. would have to get through more glass than needed. and that car tint stuff is not a measure of reflectivity. its transmittance.

as for ventilation, i am making a reflector and putting a sort of glass shelf underneath of the light. the heat will be vented this way. i dont expect a problem with heat considering the airflow the lamps will have. the tubes are a neat idea.

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Environmental chamber design and construction
Super Silver Haze Hydro Grow
SSH grow v2.0 "Full Auto"

Europa

Ocelaris,
Welcome back, and thanks, we can use all the help we can get. What do you think the benefits of that tube are versus a regular reflector/plate glass hood? When I checked out the MH's I noted that a lot of the heat was radiative, not just convective. It would be great if we could find a material that reflected or absorbed far-IR but let the near-IR, UV, and Vis pass.

Sputnick,
Yikes, where to start???

Sput, it's going in the cutout in my bedroom. It will provide light only a few hours a week, sort of light therapy for these dreary winters. So, not enough to worry about light loss.

The idea of bifolds was to allow us to keep the chamber relatively deep, without having to sacrifice depth to get the doors open. The bifolds should be store bought, say clear pine, mom wants this stained walnut and polyurethaned to match the woodwork in the basement. The outside front header and kickplate should also be clear pine but the rest can be whatever plywood and boards you want. It's probably not going to make it through the door so it only nees to be sturdy enough to pull out and clean behind.

The plexi (lexan, whatever) can be epoxied to long hinges or we can build a frame from angle-metal (Al). Attaching the mylar/blankets to the shade is a good idea, it will help strengthen the flimsy plastic. Again don't worry about light lost around the edges, although we'll definately need to lightproof the bifolds, that spongy stuff should do the trick.

Ocelaris

Europa,
I'm not sure, but I believe that most of the far IR is absorbed after leaving the glass shroud that encases the actual light emitting part of the bulb... I believe that most glasses will absorb frequencies on a similar basis that the glass shroud of HID bulbs does... Or maybe it's special glass? I think all that matters is getting as much light as close, and as directly from the light source as possible, that's my only problem with the glass sheath "bake a round" idea. So if maintaining spectra is the focus, then I think you should aim for nothing but straight MH/HPS bulbs, as in no glass tubes...

here's a neat article on Halides:
http://www.gaash.com/html/articles.htm

As for why Halides have more radiative heat, I would guess it's because of it's broader spectrum than HPS? Does that make sense? Especially since it has more blue energy, it's frequencies are longer, and would penetrate further. I mean that's why alot of deep water corals have adapted to blue light, because that's the only part of the spectrum that will make it that far down in the water. That's just my guess, but to me that's inconsequential, just that If I need the spectrum of a halide, I've given myself upto all their faults. I wonder if Borosilicate glass (pyrex) absorbs different frequencies than "normal" glass, like a hurrican candle lamp?

I've attached a diagram which I think is as suitable alternative to the glass tube idea. This way the lights can move up and down, assuming that you put the inner box on some sort of pulley system, and the heat goes right up past the bulbs. This is not feasible if you're planning on using CO2, because it assumes the influx of outside air for cooling.


I think to me the question is heat containment. Certainly that to me is the biggest problem, when you start talking about enclosed spaces. If you're using CO2 you have to contain the CO2, but if you're doing without CO2, then probably it would make sense to take advantage of the exchange of outside air.

That is a question I wonder, what would the requirement for air exchange be if you could keep the temperature and humidity down?

And Europa or Sputnick whomever is the chemistry wiz, maybe you can answer this one for me. I've always considered the bubbler idea a very simple effective way to do hydroponics. I like the idea, but recognize through my aquarium hobby that most of the exchange of oxygen and dissolved gases happens at the surface, and that the air stone bubbles themselves do nothing except to agitate the surface. What if you could do some oxygen saturation directly into the nutrient solution? I realize that this would raise the ORP significantly, and probably lock out many nutrients due to oxidation. Is that correct? I'm just thinking about an ideal nutrient solution, would it be possible to dissolve pure O2 into a nutrient solution for plants? I know that there's a big market for Oxygen regulating equipment, just curious as to the chemical aspects, What's your thoughts on that? Could you theoretically do away with external venting if you could add CO2 and O2 to the chamber? Thanks, Ocelaris

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Europa

Ocelaris,
What I meant by radiative is that besides the heat rising with the air currents there was quite a bit of heat felt below the lamps. I didn't see any HPS in action so I couldn't compare. I did some calculations for another thread regarding proximity of the lamps to the plants and don't believe that moveable lamps are necessary in a veg/flowering chamber. I think, as you say, we'll will start off with just the bulbs.

proximity

No CO2 for this bedroom, asphyxia can cause death. I have enough with all the dog farts to start worrying about CO2. You're right about the O2, by increasing the partial pressure of O2 in the bubbles and thereby in the atmosphere above the nutes, the amount in solution can be increased 5 fold (1atm @ ~20% --> 1 atm @ 100% O2). However, a stuck valve on the tank or power outage on the exhaust and we'll have quite the fireball. I want to smoke it, not the reverse. So, not worth the risk for a few Z's.

I've read somewhere (aquarium info I think) that with fine bubbles and at room temp up to 90% of the O2 in the air can dissolve in about 1 foot of rise. So lots of fine bubbles should easily be able to keep the solution aerated. Also, keeping the solution temp at RT will assist the solubility of O2 in water, but not much. At 20% O2 and 1 atm the solubilities are 0.000005 and 0.000004 mole O2/moleH2O at 20C and 30C, respecitively.

Also, regardless if we use air or O2, oxidation of ferrous iron to ferric rust is going to happen but it can be suppressed with the addition of EDTA and slowed by preventing the solution from getting too warm. This is one reason it's good that the nute reservoir is going to be on a concrete slab in an unheated part of the basement, it stays cool all year.

If I missed anything let me know.

Ocelaris

Europa,
Not to distract from the Discussion, but I noticed you grow orchids? me too! coincidence, I think not, a couple of people here have related hobbies. Just curious what kind of setup you have for yours? I have a probably 20 orchids of varying sizes under a 400w 6500k MH light, some odontocidiums, cattleyas, one odontobrassia, one or two phals, one specias valenosa (sp?), and two dendrobiums. I have them hooked upto a timer, which mists them 3 times a day, and have some exhaust fans. Some of them are doing better than others, mainly because the medium is all screwy, some are in all grow rocks, and some are in all bark, so I need to go back and repot all of them some time, and figure out a better way to mist them all equally without spraying any one too much. But, they seem to be doing well. It's Sharry Baby blooming time, my favorite Oncidium hybrid, smells like sweet chocolat :-) yum. Best, Ocelaris

Europa

Here's my grow thread, you'll see where everything is now.

Europa's grow

I can never keep track of what's still alive (I've killed so many) but they include, Oncidum, Cattleya, Saphrolaeliocatleya, Odontocydium, Brassolaelia, and Dendrobium, yes I too have Onc. "Sharry Baby Sweet Fragrance". Mine are just starting to spike now. I have a few on a window sill too.

Ocelaris

For your Viewing Pleasure, and testing out my new photoshop skills... alt.binaries.e-book-technical has a photoshop howto book posted a few days ago. you can see the misters in the roof of the grow tent. Ocelaris

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sputnick

ooh purple...nice to see you have ugly leaves like europa. his plants often times look like they are dieing very slowly. just the way orchids are he says. i imagine his plants could yield some pretty flowers. wouldnt know though. only ever seen the yellow ones on the long spike, and those small dark red ones. just messing with you europa. ocelaris, how often do they bloom for you? europa's environment seems much less "rain forest" than yours. some pretty plants would be nice to have in my dorm room.

Hmm. so a recap on what is going into the box might be nice.

Lighting, cab features, dimensions, venting, and how the physical side of the growing (bubbler stats)...i will write up something in a bit. got some math work to do and an oral presentation to write. among several other assignments...oh boy...back to work

__________________
Environmental chamber design and construction
Super Silver Haze Hydro Grow
SSH grow v2.0 "Full Auto"

Ocelaris

Not to deviate too much from the growth chamber, but orchids are a completely different creature. And Europa is right, Orchids are such an old species they don't have all the same adaptive and as i like to think of it, dynamic foliage as more modern plants. By this I mean they do look like they're dying because they don't make much foliage per plant... Like per psuedobulb they may have only 1 or a couple leaves. and those leaves are permanant, they don't just grow new internodes.
The only other plant I've grown indoors is a tomatoe plant, and I imagine MJ is very similar in that it's really fast growing, compared to orchids. Depending on species, the best ones bloom once every 3 months, and the worst ones are seasonal, so like sharry baby is an oncidium hybrid from somewhere in south america (or at least it's heritage is from there), and that being the case it's just warming up there, and so spring time brings out sharry babyy, even though it's fall for us. I think it's really an acquired taste, because orchids grow so slowly, you can't tweak your plant every day, you have to shoot for the best environment possible, and leave it there. If anything Orchids don't like to be played with.
Anyone ever thought about that, like older species of plants only survive in the tropical climates? It would seem that a better climate would create more highly evolved plants, but really you only see adaptation where it needs to be, like in the colder seasonal climates, and in the rainforest... Interesting how evolution takes a turn at the extremes and in the middle.

Anyways, Thought I'd post some more blatent promotions of my plants... hope it's not too offtopic, I mean, it is a growth chamber.

Here is an outside shot of my "orchid tent" as I call it, it has a zipper to open it up. It's not quite as sealed as I would have preferred, then again it has been an ad-hoc thing I've put together over the years. You can see a circulation fan near the front of the entrance, and a sink where the water drains into after misting the plants 3 times a day. Ocelaris

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Ocelaris

ok, here's after it "rains" I wish I wasn't using tap water, which tends to leave carbonate deposits on the "ugly leaves" <grin> but it's cheaper than buying a pressure pump to use DI water. This is with the lights on I might add.

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