Just added second Mars Hydro 1200 to Current Culture 4XL undercurrent setup..help!

Hey guys.
Just coming around to week two of flower, and now having added a second light, as well as abnormally warm winter temps, I'm now having some heat issues.


The setup is the 8Gallon version of Current Culture Under Current 6XL system, but currently running only 4 of the buckets.

With just one Mars 1200, I was able to keep the room around 75-78 degrees with only a 440 CFM 6" inline fan w/Carbon filter exhausting the air into my living room, and a 6" duct booster fan acting as an intake - roughly 15ft of duct to the closest window (The room does not have a window itself)

Now that I've added the second light, I'm up around 85 degrees without AC. In the meantime, I've hooked up a 7000BTU portable AC with the exhaust connected to a 6" wye, which also has the inline fan now exhausting air 15' total to the nearest window, and with the duct booster fan now running with a 6-4" reducer and 4" ducting 15' to the window.

The AC is keeping up, but just barely. It's also been something like 80degrees ambient in our tropical, landlord controlled apartment.


I feel as if I'm not set up correctly...with the inline fan basically sucking out the cool air as the AC does its thing.

Should I be circulating the inline fan/carbon filter back into the room and using the duct booster fan to help exhaust the AC?

Please advise!
Thanks,
S

Not really much you can do except upgrade your exhaust / AC. I had the same issues and damn near got tarred and feathered by the Mars fan boys when I bitched about it. My thinking is, if you need to run the same environment controls as a HID setup, why spend all that money on a few fixtures that will yield less and not last as long ? I really don't see the efficiency in that at all. The only way I will try LED again is if I build my own with cree chips

Forgot to mention the room is 8x10, but roughly sealed off with black/white panda film. Lights are about 15" above canopy

Here's a rough sketch of current setup

That setup is correct though? With both running through the wye?

If I'm looking at it right , no it is not correct. It looks like your AC is connected to your exhaust ? If so, how is the cool air doing anything ?

If it were me I would remove they wye and run the fan and filter straight to the exhaust. Add a circulation fan of two, and maybe place your intake on the far left side away from the fan. That way the intake air would have to move across the entire garden before being exhausted

there is one 6" duct going from the room to the window.

Connected to that is a wye, with the 6" inline fan / carbon filter on one side, and the exhaust from AC on the other.

the carbon filter is on opposite side of the room, so the cooled air is traveling across the canopy and out via the carbon filter.

does that make more sense?

Nevermind I see what you did. If I were you I would still remove the wye, place the AC on the side of the room away from the exhaust fan and see if that helps.

Yeah that makes sense, if that isn't working your exhaust just isn't big enough. I had the same frustration bro. Mars markets there lights like they run cool and efficient but it's all a bunch of bullshit. Hopefully you never have to use them for the warranty because there horrible to deal with

ive been pretty happy with their light so far. grew over a lb of white widow in a 4x4 tent for my first grow. had all sorts of heat issues, but our apartment is like 90 degrees in the summer so.. that part sucks.

I'm thinking to ditch the intake and go with an 8" fan and duct after this grow. Probably time for a bigger AC too

..

What is your leaf temperature? I understand that with HID the leaf temperature is roughly 80-85 anyways in a 70-75 air temperature room but with led the leaf temperature can be cooler allowing for the higher air temperature and not causing problems. Are you seeing any heat stress? If you're running co2 as well I bet you are maximizing the photosynthesis at that temperature as long as your leaf temperature is not too high.

Limeygreen said:

What is your leaf temperature? I understand that with HID the leaf temperature is roughly 80-85 anyways in a 70-75 air temperature room but with led the leaf temperature can be cooler allowing for the higher air temperature and not causing problems. Are you seeing any heat stress? If you're running co2 as well I bet you are maximizing the photosynthesis at that temperature as long as your leaf temperature is not too high.

Click to expand...

I've changed the setup a couple times since initial posting. Last run with two mars 1200s and 8" exhaust fan, 6" intake (and eventual 6" duct booster) worked really great last winter, so long as it was 55 degrees or less outside. Was mostly maxing out around 85degrees which, after some more research apparently is pretty much the sweet spot for LED. I did manage to keep it down around 70-75degrees in flower and the buds came out really great.

Currently setting up a new run with LEDs ive built myself using photon phantom designs wavy boards. Seeds are vegging under t5, will eventually switch to a 225w (3) 3590 LED bar i grabbed from timber grow lights, vegging in 4" rockwool cubes. those will then get dropped into current culture 6 bucket RDWC system for a couple weeks and flower. Trying to figure out how to really dial in this Link4 iOponic 624.

I'll probably post a new thread and update once I've got some content. Really excited to make some of the changes I wanted from the last run.