Another "kool tube" thread

[daniel_fox_grow]

I have designed a grow box that is 4 sq. feet for use with a 400 watt HPS light.

Since my box will be entirely closed, I am curious to know if it would make sense to draw in and then expel the air from outside the box at both ends.

That is, most kool tubes designs I have seen do not fully isolate the air flow from the grow room or grow box. In fact, most kool tubes simply open into the grow space and rely soley on a 250 cfm or similar fan to pull the heat back through the tube and out of th room.

Is mine an uneccesary concept? Apparently kool tubes are a very effective means of heat transference so maybe the enhanced design is overkill, but I like the idea of a grow room that is as controlled as possible.

Another aspect of my original box design was to use a sheet of plexiglass to seperate the tube from the plant even further. In my consideration of a desing the plexiglass sheet, placed at 3 ft, would allow for a CO2 enrichment environment. I do wonder however, if the grow room air would become stagnant under any of the conditions I have described here?

Thanks in advance for your advice.

[Poco 9]

to your cool tube question I know for a fact that it would not hurt to draw air and exspell air from out side the box.. my room had six cool tubes all connected to each other and I had a high powered fan draw the air from outside through the tubes and the heated air was vented outside made for a better grow and also a controled temp grow..

as for your air in side your box going stagnant as long as you have a good intake of fresh air and a good vent to exspell it you should not have a problem.. I got a damn hot looking lady in a box 24" x 24" x 5' high with a small computer fan blowing down across the shroud and into the box and my temp is a constint 76 degree's and she LOVEs every moment of it.. you just have to make sure they get the fresh air and vent the bad.

from there you should know how to handle it...

Happy Growing
poco 9

[CloudyBongWater]

Hmmm... I'd say that sounds like a really interesting idea. The only real hole in it that I can see is that I don't think your 400w light puts off enough lumens in 4 sq ft to really make CO2 enrichment helpful. But I can't remember how many lumens a 400w light puts off. Take the lumens and divide by four... if you don't get at least 10,000 lumens per sq ft, then they say it isn't a benefit.

If you don't use CO2, then I wouldn't hassle with the plexiglass because you'll need to lower and raise your light too much. As for the intake on your cool tube... it doesn't matter too much which you choose... fresh air or air from your growroom. Last grow I used the air from my growroom... making it my exaust.. then I only needed an intake fan. Next time I'm hooking a fan to each side of the tube (one pushing, one pulling) just in case one fails.

I'm stoned, so I hope I'm making sense (some would say for the first time). Good luck!

CBW

[The_Undertoker]

I just purchased a cool tube as well. For fire safety the 600 watt hortilux will be hooked up to a thermostat which will turn the lamp off if the temp in the box gets above 105 degrees or so.

[The_Undertoker]

FWIW

Some think CO2 enrichment is useful even at lower lumen levels.

Also even with a CO2 setup, you need to expel the old air once in a while. You can set up a ventilation fan on a timer that turns it on for 15 minutes every couple of hours.

$.02 The plexiglass is probly an overkill.

[CloudyBongWater]

Yes, do your research on the CO2 before making a final decision. Undertoker could be right. I'm just relaying what I've read from other posters... I can't back it with any scientific evidence and don't know that much about it beyond what people have posted.

Good luck,
CBW

[Quasi]

To really reap the benefits of co2 your grow space should be air tight. The co2 should be injected or w/e from above, since it is heavier than air and will settle down low. But if your temps go above 100 F you will have to vent the hot air from higher and bring the cooler air in low. It might be a good idea to tinker with it before putting the plants in there. A fan or two down low will recirculate the co2 but all of the co2 should be vented at lights out and fresh air brought in. For co2 to be effective your lumens must be 7500+ psf and temps should be between 93-98, with 100 F being the highest. Watch your humidity at those temps too. It is all about excellerated transpiration. Good Luck, should you choose to use it. I use co2 when my summer temps get above 92-93, but my setup is not really ideal for co2 but the added co2 seems to help the plants from wilting/drying at these temps. I'm buzzed, so if this sounds like gibberish, so be it!.

[daniel_fox_grow]

Good advice all. A versatile grow space is what I am after. THanks for all the extra CO2 info too.