Cooling 1000w hps 4x4

I got a 4x4 grow tent with 1000 watt light inside of it my temps about 20” under the light are high 80s no issue with veg but when I flower that needs to come down to at the very least 75 so I don’t loose potency or slow down bud growth what can I do to help this? I have a 8” fan hooked up to the light and a 205 cfm fan sucking hot air out to get maximum air exchange but im still at 85

Portable a/c

Where inside my tent?

Buddernugs said:

I got a 4x4 grow tent with 1000 watt light inside of it my temps about 20” under the light are high 80s no issue with veg but when I flower that needs to come down to at the very least 75 so I don’t loose potency or slow down bud growth what can I do to help this? I have a 8” fan hooked up to the light and a 205 cfm fan sucking hot air out to get maximum air exchange but im still at 85

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Get a bigger fan. I run a 600 watt HPS in a 4 x 4 and I use a 400 cfm fan. If you don't already have one get a sealed hood.




I've ran a portable AC in the tent before but it takes up a bunch of space and then you have to exhaust that as well. Now I just shut down the flower tent for a couple months during the summer and grow a few plants outside. Last year the weather here turned to crap so I finished the plants off inside in the tent. It worked out pretty good. And I'm going to do that again this year. The benefit to that is using the sun and being able to grow strains that won't finish outside. I'll just bring them inside when the summer heat is gone and can run the tent.

I have the 8” xxxl sun system hood hooked up to a 8” inline fan but I need to control the Oder so one side is sucking air out the tent other is being pulled into my carbon filter... should I use the 8”for air exchange and get a 6” with a adapter and use that to suck air from out side the tent inside the hood and then out side the tent?

You only need one fan and passive intake. Meaning you have the vents on the bottom of the tent open. Filtered of course so you don't suck crap into the tent and contaminate your bud.

Then Filter - Fan - Hood - Exhaust out like the photo I posted above. You can suck the air through the hood but I prefer to push it so the fan isn't taking all the heat from the light. You need a higher CFM fan, exhaust out of the grow area.

thats what i would do, use the bigger one for the air exchange and filter. calculate your cfm lxwxh then divide that by 3 3 being the amount of times the exhaust completely exchanges the old air for new air. typically 3 to 5 times an hour works well. i also like to add
For every 1000 watt of HID lighting, add 10% to your CFM rating.
If you use a carbon scrubber, add 20% to your CFM rating.Add 1% for every foot of duct tubing you use to connect your exhaust fan to the scrubber.
xtsho knows whats up

Open windows in basement lights on at night my canopy temps (Lasered) are 73-77, ambient temp is 80 hopefully that will work in flower without hurting my yield

why wouldn't it. sounds good to me

Word thx man what should I hang at I have it at 27” but I’m seeing signs it might be to close what do you think

depends on the bulb brother...i would just watch the them and how they respond to it....i always start high and gradually move it down. your def in the ball park just gotta find that sweet spot i got a 400w im at 12 they love it i try and get as close as i can wijthout hurting them of course

Swap the 2 fans, or just use the 8 inch alone
and exhaust through the hood instead.

I raised it to 32” the one was getting twisted but the older one was fine

Deff need more than 205 cfm, I’m using more than that with leds

I have a 8” 750cfm fan hooked up to the light hood the 205 cfm is for boosted air exchange also I have a 475 cfm carpet fan blowing directly into the tent via a sealed Duct so I’m getting a shit ton o fab air movement inside that tent my temps this morning after 11hrs on was as followed...ambient tent temp 65 canopy temp lasered was 72-73...light on black surface on edge of pots was 80 I have 5 temp gauges in that tent I’m just going to have to stay on top of it for now one thing I’m realizing is no mater how much cool air u have if the plant can’t take the 1000w of light it won’t help I have my light at 32 inches above canopy with about 10” of height to work with so 42” total so I really hope I didn’t waste money on this light set up I hope as they stretch in flower mode they will become more resilient to the 1000w being thrown at them as of now they are about 8 weeks old I flipped the switch yesterday we shale see... I’m deaf going to have to lst them To keep them as low as possible that’s for sure... fuck it tally ho....#fullsend

Switch to leds lol 1000watt bulb in a closed tent is gonna b hard and if ur having these problems now it’s still cold out only gonna get hotter and hotter

I was at leds I switched

Old caustic we use to use

vents open at bottom and have filter/fan out side of tent pulling air... have a box fan blowing direct heat from between tops and light towards outtake.

I'm sorry but someone needs to say it a 1k in a 4 x 4 is too big
Either go back to LED or buy a 600 or cmh
Either that or you drop bank on an a/c