Can't Keep Temps below 90-100F

GRRRR I just broke my bong too !!!!

All you haters, your giving me bad karma lol

Hm, the loam of your soil looks odd to me. What brand did you get? Tilth means a lot in soil growing. Also, your set up is a nice looking cabinet grow. With a good enough exhaust it should be fine, I'm not sure what is causing your temperature to be so high.

I used Promix Multi Potting and Seeding Soil

Would have liked to try the fox farms stuff but couldn't find it anywhere, and from every Toronto grower i've talked to/read from they say Promix is fine *shrug*

Its very dry at the top, is that perhaps what your seeing? I'm trying to let them go as dry as I can really cuz of the apparent overwatering thats the only thing I can think of to cause them to droop like that

Last batch of FFOF I bought wasn't that great, I no longer solely recommend them haha. When I grow soil I'm overly hippy organic and sustainable. When I grow hydro I grow fully sterile with no organics. People love to see me jump between the 2. My favorite grow method of all time. A well established aquaponic system *drool. I had to destroy mine after I moved so I won't restart one until I'm settled in a permanent establishment.

aquaponics? isnt that like in a fish tank?

http://en.wikipedia.org/wiki/Aquaponics

Not even close haha ^_^

Yeah i'm gonna be growing them in Canna Coco, only reason I started them in potting soil is cuz i've had nothing but failed grow attempts in the past lol, so I wanted something that would get em growing for sure. Also I was unable to find a straight answer/info on whether or not you can just plant seed right into coco.

I still don't know if its a good idea to transplant them into coco (they will be in 10 gallon pots), but thats what I want to try anyways (6 are going outside, i'm talking about the 2 im keeping inside obviously heh).

Either way i'm looking forward to trying the coco 'at some point' cuz ive heard really good things about the CANNA brand coco, and also have the Canna A+B nutes, so I figure ... i dunno, fool proof lol (i'm a chemist by trade so .. pHing stuff/modifying molarities etc. is in my nature heh, I got a good pH meter and a good TDS/EC/PPM/BLAHBLAH meter too)

I really wanna try DWC at some point (well at the very least a form of NFT with sprinklers inside like 4" PVC), but that was way out of my budget this time, not to mention fairly complicated for someone who still hasn't had a successful grow (2 failed attempts .. third time's the charm?)

guitarguy10 said:

I built a grow box in a dresser (3.5' H, 2.5' L, 1.5' W).

The lighting is with a CFL fixture I built out of PVC pipe.
It consists of 10 23W CFLs

I have 2 x 120mM 12volt fans, 1 intake on the bottom and 1 exhaust near the middle back of the box (can't put it at top, be a DEAD give away to the grow boxes existence), and an oscillating fan inside.

They are still babies (grown from seed), so its hard to say how they are reacting to these temps, but most of them are drooping pretty bad (they are growing very fast however, with almost NO lateral growth between each set of new leaves).

With the lights on and dresser closed temps approach 100F. They are typically stable at 92F though, which is ... way too high.

When the dresser is COMPLETELY open the temps dip to 82F which is still WAY too high for me, esp. with the box completely open.

I thought these CFL's wouldn't create any heat problems, but apparently they do (its a good thing I didn't put my 400W MH in there).

Ambient room temperature is 65F, thats a delta of over 25F, so I don't know whats going wrong.

Any advice would be greatly appreciated.

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2 fails.

1- you lack enough airflow for that many lamps.

2- this isnt a jet engine, we dont use intake fans... ever. always use passive intake (aka as a vent) one fan pushing and one fan pulling creates cavitation on the fan blades, which in turn greatly reduces the ability of the fan to move air...

another thing to consider- wood is a terrible conductor of heat... in other words, once it warms up, it tends to stay warm... so your also dealing with a radiant heat issue, as well as lack of decent airflow.

you would be better off with 2 exahuast fans.. instead of a supply and exhaust fan.

Ambient heat! There we go.

Also in terms of negative pressure you are right in terms of the exhaust losing cfm but people use it in conjunction with carbon filters. Personally, I don't follow this but it's a common practice.

IAm5toned said:

2 fails.

1- you lack enough airflow for that many lamps.

2- this isnt a jet engine, we dont use intake fans... ever. always use passive intake (aka as a vent) one fan pushing and one fan pulling creates cavitation on the fan blades, which in turn greatly reduces the ability of the fan to move air...

another thing to consider- wood is a terrible conductor of heat... in other words, once it warms up, it tends to stay warm... so your also dealing with a radiant heat issue, as well as lack of decent airflow.

you would be better off with 2 exahuast fans.. instead of a supply and exhaust fan.

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1. Each fan pushes 90CFM (these aren't cheap no-name PC fans heh), so your saying 180CFM isn't enough to cool 10 23W CFL lamps?
2. Someone on another forum also suggested making the intake an exhaust (I had no idea, I figured pumping COLD 65F air from outside into the box wouldn't contribute to heat, I guess I was wrong *shrug*). I have flipped the intake around so there are now 2 exhaist, but the temps have gone UP (I wanted to try this before cutting another hole in the box ...)

A passive intake brings in cool air without a fan to even out the pressure, negative pressure is a theory for use with a carbon scrubber. With the heat issues, as long as you have a passive intake, try flipping it to an exhaust to see the temperature difference.

*edit* didn't notice you already flipped it. I can't see how the temperature would go up unless there was no passive intake, if not yes it would go up.

your a chemist....and u cant grow pot? .....

... how are those 2 skills the same thing wayno? I'm an interpreter by profession but I can't break down a language with linguistic jargon. 2 areas of study, all this chemistry would be useful for is analyzing nutrients and understanding chemical reactions. Does not mean he knows plant biology, hydroponic/soil sciences.

I know a master gardener, she has the biggest personal garden I've ever seen (she's an avid organic/sustainability hippy) yet she has never grown pot. Shee learns how to grow each plant individually, applies general soil knowledge but all plants have different lifecycles and I'm sure if she picked up growing cannabis after a few years she'd be a pro. Wouldn't top hobbyists who have been doing it awhile on the first go, regardless of the amazing topsoil she's created over the countless years.

wayno30 said:

your a chemist....and u cant grow pot? .....

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but can he make LSD?

most eexpensive drug by weight ever!

wayno30 said:

your a chemist....and u cant grow pot? .....

Click to expand...

To further prove my point, it's you're. You grow pot and you can't spell? (Bit more extreme)

insomnia47 said:

but can he make LSD?

most eexpensive drug by weight ever!

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rofl! I'm sure it'd be easy to synthesize LSD for him, would he want to though?

The point I was trying to make was that when dealing in PC fans and CFLs exhaust is really not about air exchange for the plants... rather getting the hot air out as fast as possible. Yes, you will have smell issues (at least if you plan to flower there, if not it will not be that bad. Plus the rate of exhaust isn't going to matter)

Three 90 CFM exhaust fans would not be overkill in terms of heat exhaust. Firstly, the CFM ratings on PC fans aren't accurate and you do not have to worry about the negative pressure imploding your box. I grew in 13 cu feet with 416 w of CFLs and was able to keep my temps in the low 80's. Double and triple up on your exhaust and watch your temps drop. You will not kill your plants with the negative pressure. As far as the passive intake...you may want to add a small one in conjunction with your active intake, but I think you need at least one active to keep the temps down. Also, a small squirel cage fan to blow upwards on the lights helps...

EDIT: I saw your hood...while it's cool...it's restricting airflow and probably heating up in that small space. My rec would be to ditch it.

MasterS said:

rofl! I'm sure it'd be easy to synthesize LSD for him, would he want to though?

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well considering that 1 gram is capable of making 10,000 doses at 3$ a pop, thats 30gs just for 1 gram. if i knew how i would, thats one hell of a profit

wayno30 said:

your a chemist....and u cant grow pot? .....

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Correct

I have never grown ANY plant before, so pot, tomatoes, i'm no botanist, and so far my overly zealous analytical nature has been what's created all the problems in growing.

Thanks for kicking me while i'm down though, I definitely get this warm and fuzzy feeling being reminded that I can't grow a plant that I know children are capable of growing.

I possess the skills necessary to make LSD, but to get the ergotamine or related analog precursor is next to impossible, and the synthesis itself isn't very fun, as LSD and its intermediates are highly light/temperature sensitive.

If I were to put my chemistry skills to any use it would be to make MDMA, which is a far more .... 'beautiful' organic compound (3'-4' methoxy bridge, take that brain, lemme see you metabolize the 4' phenyl moeity of a phenethylamine with internal aromaticity of that 4' phenyl position !).

Overall though i'm not interested in putting my skills to these ... uses.

Hm, is it easy to obtain Safrole oil in Canada? If so I'm moving