Grow tent 600w hps hydro under construction

laserbrn

laserbrn

Well-Known Member
anon1122 said:
Well, my reasoning was that if the fan is sitting on top of the filter on the outside of the tent, and the ducting goes up and onto the top of the tent and then down into the duct hole and then attaches to the hood, i put my hand on the other side of the hood that was open and you could feel it pulling some air, but it did not make the tent concave.

When the filter and fan is inside the tent, all sides of the tent are sucked in and there is forceful air coming out of the exhaust ducting. So it would seem to be more efficient this way, but I am a newbie so I could very well be wrong.

I read somewhere that every bend in the ducting makes you lose air pressure. I think that because the fan is trying to suck with pressure through bends and at least 10 feet of ducting that it is losing significant pressure. Therefore not moving as much air out of my tent.

Im thinking now about keeping the fan and filter in the tent and just running it through the hood on the way out. seal up the flanges of the light where the glass is with duct tape and vent it that way. I know that you said it is a 2 degree difference whether pull or push but at least I'd be doing something about cooling the hood.

Thanks for taking time out to help.
Click to expand...
That's interesting. You definitely need to have as few bends and as short a run as possible for the fan to run efficiently. I don't have 10 ft of ducting as my Can 66 Filter is pretty tall. The hole for my tent is also not on the VERY top, it's on the upper portion almost parallel with my light so I don't have a "U" shaped bend on mine. I'll bet that would kill my idea. A combination of a shorter filter (further distance) and much more drastic angles and bends in the ducting.

The only thing that I can think with the pushing vs pulling is that when you pull air through the lamp it sucks away the hot air before it has a chance to hit the glass. Very little pressure from hot air on the glass lens. When you push it you are creating MORE pressure on the glass from hot air causing the glass to heat up.

Could be way off base. I'm only basing my assertion on trying it both ways and testing the temps.
 
smokingrubber

smokingrubber

Well-Known Member
Anon,

Can you confirm the size of duct holes in your tent? I want to use my 8" fan, so I will buy a hood with a 8" hole and the same size filter. I just want to make sure everything is going to fit.
 
B

Bob Smith

Well-Known Member
smokingrubber said:
Anon,

Can you confirm the size of duct holes in your tent? I want to use my 8" fan, so I will buy a hood with a 8" hole and the same size filter. I just want to make sure everything is going to fit.
Click to expand...
Most tens only have 6" flanges, but that's easily fixable with a $2, 8" to 6" reducer at Home Depot.
 
smokingrubber

smokingrubber

Well-Known Member
I tried reducing the 8" fan down to a 4" dryer vent and that totally did NOT work. Well, it worked in principle but it certainly didn't move enough air. If the holes are 6" then I should buy 6" stuff and save or sell the 8" fan.
 
laserbrn

laserbrn

Well-Known Member
smokingrubber said:
I tried reducing the 8" fan down to a 4" dryer vent and that totally did NOT work. Well, it worked in principle but it certainly didn't move enough air. If the holes are 6" then I should buy 6" stuff and save or sell the 8" fan.
Click to expand...
I definitely wouldn't hook up an 8" fan to a 6" duct. You need to run some temp tests because I don't think you have as many problems as you think. An 8" fan is GNARLY for a 4x4 space. I would get a 6" reducer and just run it like that if the tents holes are applicable. Don't you already have an 8" flange on your filter, an 8" air hood and an 8" fan?
 
anon1122

anon1122

Well-Known Member
The holes on the upper sides are 4" the ones on top are 6". I have a 6" valueline fan and a carbonaire 6" filter. the filter is 22"tall 15" in diameter and weighs 55 lbs. she's a big bitch.
 
tea tree

tea tree

Well-Known Member
I have an eight in valueline fan on a six inch duct for my 8 in cool tube that a 600 watt lumatek powers. It works great. All this in a 4x4x6 tent. I tried it with a six in valueline first that I use to cool my 400 in a 4x4x6 tent and it was not powerful enough for me. I exhaust all this straight over an ozone generator then out the house into the desert air. Lol, it gets a little mixing first then out. I tried a htg speed contriller on my eight in and it works when the light is off but pointless when on and the fan makes a funny hum when I reduce the power. SO IDK save your money and dont get one. Keep the eight inch. It is a goog investment on a light for sure. I have always beleved in the biggest fan I can allow soundwise. Lightbleeching becomes my concern. :)
 
anon1122

anon1122

Well-Known Member
Ok, temps hold at the low to mid 70's all zipped up with the ventilation the way it is. I think it will be ok. as for a screen, Im having a bit of trouble but I think I have found a design solution. The only thing I worry about is when I have to change the reservoir and I have to lift the tray up to refill it. So I am almost leaning towards not having one. I am sure I can pull a respectable harvest of at least 10-13 oz's when all is said and done. Anyone read or have any experience with bc bud depot's
"The black"? So many choices but I have to pick one by next friday, that's for sure. Any input?
 
laserbrn

laserbrn

Well-Known Member
I say go without the screen the first time. I'm experimenting with the screen. My last grow I ran without it and I got 13 zips of White Widow. I just felt I could've gotten more if I had a bit more efficiency so I'm going to try it. I might get less, it might become a huge problem later, I have no idea at this point. First go around, keep it simple.
 
B

Bob Smith

Well-Known Member
tea tree said:
I have an eight in valueline fan on a six inch duct for my 8 in cool tube that a 600 watt lumatek powers. It works great. All this in a 4x4x6 tent. I tried it with a six in valueline first that I use to cool my 400 in a 4x4x6 tent and it was not powerful enough for me. I exhaust all this straight over an ozone generator then out the house into the desert air. Lol, it gets a little mixing first then out. I tried a htg speed contriller on my eight in and it works when the light is off but pointless when on and the fan makes a funny hum when I reduce the power. SO IDK save your money and dont get one. Keep the eight inch. It is a goog investment on a light for sure. I have always beleved in the biggest fan I can allow soundwise. Lightbleeching becomes my concern. :)
Click to expand...
I currently have two 6" in my 4x4, one strictly for light cooling and one strictly for exhaust pulling through a filter, and then a 4" inline for intake, but if I could do it all over again, I'd probably just go with one 8" for both light cooling and for room exhaust and then stay with the one 4" for intake.

Less shit to hang, mainly.
 
laserbrn

laserbrn

Well-Known Member
Bob Smith said:
I currently have two 6" in my 4x4, one strictly for light cooling and one strictly for exhaust pulling through a filter, and then a 4" inline for intake, but if I could do it all over again, I'd probably just go with one 8" for both light cooling and for room exhaust and then stay with the one 4" for intake.

Less shit to hang, mainly.
Click to expand...
I can't belive you need that much ventilation for a 4x4. Assuming it's 8 ft tall it's only 128 Cubic Feet.

If both of your exhaust fans are 340CFM+ you're wayyyyyyy overdoing it.

128 Cubic Feet and you've got ~600-700CFM exhausting it (you lose some on the carbon filter for those paying attention to numbers).

Overkill city. 1 6" exhaust and no intake. 360CFM on a 128 Cubic Foot space is going to be plenty.

More isn't always better. It'll keep it cooler, but the law of diminishing returns will kill you. Your now using a lot of extra wattage for no reason.

6" HO fans run ~ 140w
4" HO fans run ~ 70w

so you're running in the neighborhood of 350w for ventilation. That's killing efficiency.
 
smokingrubber

smokingrubber

Well-Known Member
laserbrn said:
I definitely wouldn't hook up an 8" fan to a 6" duct. You need to run some temp tests because I don't think you have as many problems as you think. An 8" fan is GNARLY for a 4x4 space. I would get a 6" reducer and just run it like that if the tents holes are applicable. Don't you already have an 8" flange on your filter, an 8" air hood and an 8" fan?
Click to expand...
The 8" hood & filter are installed on the other grow. I have one 8" fan left over that I want to use on a new tent. I will have to get a new hood, flange and filter for the new setup.

I think I'll buy everything 6" inside the tent, then run it out to the 8" fan with an adapter. I can just put it on a speed controller. If it doesn't work, I can buy a 6" fan later.

It can't smell though. I'm in a condo and everyone's mailbox is right outside my garage door.
 
laserbrn

laserbrn

Well-Known Member
smokingrubber said:
The 8" hood & filter are installed on the other grow. I have one 8" fan left over that I want to use on a new tent. I will have to get a new hood, flange and filter for the new setup.

I think I'll buy everything 6" inside the tent, then run it out to the 8" fan with an adapter. I can just put it on a speed controller. If it doesn't work, I can buy a 6" fan later.

It can't smell though. I'm in a condo and everyone's mailbox is right outside my garage door.
Click to expand...
Sounds like a good plan. It's not going to smell. I live in an apartment and I can't smell a thing anywhere. It's the carbon filter that's going to dictate that, not the size of the fans.

It's a matter of not having any leaks and maintaining negative pressure. You are going to be FINE. I have the stinkiest buds around and the 2 people I actually showed it to couldn't believe it had been there the whole time. They had no idea, no odors, no problems.

I did have a little left over smell when I had my veg room up and running because the plants were stinking in there, but like I said, Ozone Generator stopped all secondary smells. Killed'em dead. Smells like a clean rainforest.
 
anon1122

anon1122

Well-Known Member
Can't ozone generators be detrimental to human's health though? I would like a back up, but everything is in my bedroom.
 
smokingrubber

smokingrubber

Well-Known Member
First, I was just checking the stats on the GL145 tent (the one Im getting) and it says it has 5 - 8" ports. That's perfect. I can go with 8" front to back. I'll still get the tent set up and measure everything first before I whip out the visa.

Second, talk to me about this ozone generator. I've got one (it came with the going-out-of-biz packagel that I got on craigslist). I've heard that you have to set up a seperate room to vent through or something like that. Probably wouldn't work in my garage, but my friend vents to his crawl space. Could we just plug it in down there and let it do it's thing? He has the filter going, so it doesn't smell now, but the ozone would be good backup.
 
B

Bob Smith

Well-Known Member
laserbrn said:
I can't belive you need that much ventilation for a 4x4. Assuming it's 8 ft tall it's only 128 Cubic Feet.

If both of your exhaust fans are 340CFM+ you're wayyyyyyy overdoing it.

128 Cubic Feet and you've got ~600-700CFM exhausting it (you lose some on the carbon filter for those paying attention to numbers).

Overkill city. 1 6" exhaust and no intake. 360CFM on a 128 Cubic Foot space is going to be plenty.

More isn't always better. It'll keep it cooler, but the law of diminishing returns will kill you. Your now using a lot of extra wattage for no reason.

6" HO fans run ~ 140w
4" HO fans run ~ 70w

so you're running in the neighborhood of 350w for ventilation. That's killing efficiency.
Click to expand...
Yeah, I know I probably overdo it when it comes to ventilation, but to me that's one of if not the most important factor in a grow, so I don't mind - as far as the extra wattage goes, once this electrician wires me up for 60 amps, I really couldn't care less about $10 or $15 more a month.

Also, I'm running CO2 with a 1000 watt in there, so I need to cool the light to keep temps in check while also having no exhaust going out to waste the CO2, therefore the two 6" fans are somewhat necessary for me.

I appreciate your input and agree with you, but like most things in my grow, I like to get something that can easily handle what I need it to handle - once temps get up to high and my atmosphere controller turns on my exhaust fans, it's only gonna take a hot minute for the temps to get back down and CO2 enrichment to resume.

Again, I agree that what I have is overkill, but I'm gonna go with it and see how it does.
 
anon1122

anon1122

Well-Known Member
Hanna combo meter just arrived. now for the hydroton, seeds, some pest control shit and away we grow! Am I supposed to be keeping the tip of this meter wet or something? There was some stuff crusted on the inside of the cap and I was just wondering if that was normal or important...?
 
You must log in or register to reply here.
Top