cooltube setup questions

I'm getting ready to set up a new grow cabinet and I'd like to use a cooltube with my 250w HPS. The cab is 69"x25"x16". I'll be using a pyrex bake a round for the cooltube with either a stanley blower or dayton on the end.

I want to leave one end of the cooltube open to suck out air from the cab. With the size of the bulb and the bake a round, there is only a total of 1"; of air moving around the bulb. Since the source of the heat will be directly cooled by the fan, is 1"of air movement enough to keep the rest of the cab cooled or will I need to add a 2nd exhaust to the cab?

I'm trying to keep the outlets to a minimum. It'd be a lot easier hooking up a scrubber if I can stick with one outlet. TIA

an inch is enough. most def

i use a bake-a-round cooltube with a 400 HPS in a 24x24x48 space so very similar to yours

with less then 1" of space around the bulb for air movement its enough to keep negative preassure on my grow tent, so the walls are all sucking inward - and keep the temps between 70-75. outside temp is the same.

once you set it up youll see how it completely changes the air flow in your grow space and all the air will blackhole towards the end of the bake-a-round.

i use a 4" 172 cfm vortex, probably very similar to the power of your stanley blower.

during the hottest part of the day the pyrex is cool enough for the plants to touch, and the actual HPS bulb is cool enough for me to touch although its still hot, but i can keep my hand on it without getting burnt.

i think it would be a bad idea to add a 2nd exhaust to the cab because that will mess up the air flow through the cool tube.


hope that helps

also: aluminum tape is great for attaching the ducting to the tube, and also good for patching the hole where the cord to your lamp runs through (if thats how your doing it anyway)

show us some pics when you have it all rigged up :hippy:

i was just wonderin wher i can get one of these bake-a-rounds? and i also am gon use a cooltube setup with a 250watt hps in a 36"Hx37"Lx15"W rubbermaid grow box. what do you think?

Hey Medicine,

Don't know if you're still around... but you should Check out this cab.
I'll bet it's similar to yours. The grower can probably help you out with any questions you have ;)

Hey thanks for all the responses! Sorry I haven't been around here much lately....mainly because this site is pretty slow. Been reading up on ICMag and rollitup lately.

I ended up building my box using large-sized Sterilite cabinet which the dimensions I had previously mentioned belonged to. I got a pyrex bake-a-round on ebay for my cooltube which i ended up cracking from my first attempt at rigging everything up. I tried to use hose clamps and tightened them down too much so I got another one off ebay and did it better the 2nd time around. Like you guys said, 1" of air flow definitely can create a vaccuum in my cabinet. The fan I got was a Solar & Palau TD 100x which can do 100cfm or 135cfm depending on how you wire it up.

I'm on my 2nd/3rd grow now. First one was a single lowryder 2 in some sterilite tubs which turned out pretty nice. Right now I've got a single NLxshiva that vegged for over 2 months and is now in it's 5th week of flower. I tied it down a lot so its only about 3ft tall right now. I messed up on the PH and unfortunately almost ALL the leaves have dried up and fallen off. The leaves still left are slowing going light yellow. However, its been that way for about 3 weeks now and the buds still look like they're making good progress. Not great, but I'm still expecting a decent yield.

Then I've got 5 clones from that plant that are around 2.5ft tall (no tying down yet) that I just put into flower last week.

I'll get some pics of my cabinet up so you guys can check it out. I'm pretty damn happy with the way it turned out.