No no no . you can use one fan and not have to be around for anything. You can see the fan set up i use in the pic. The intake is passive but I use a 6" alum flex tube. Its stretched out to say 8 feet along the floor in a few s turns so no light will bled up the intake. Works great and no light leaks. .
Hey any pros in here? i was wondering if i had 2 400w hps with cool tubes and both have a 6'' 250 cfm inline fan sucking air to the attic and a 8'' 325 cfm inline fan blowing air from another room into my 10 sf 6 foot tall room with 12 plants 6 in 2 dwc resevoirs with technaflora nutrients. do you think thats a good setup and do you think my yemps will be okay? like is it enough cfms? Thanks
I have a question, If I get a 400w and plan to use it in an open room (im growing autoflowers so there is no need for a grow location that hides light) will it get really hot in the room. Its an average of 70 degrees in the room and its an average sized 2nd bedroom, would I need ventilation.. or would simple fans be fine. Im only asking because I plan on working from the same room... there is a computer desk in the far corner and I will be taking calls from home... just wanted to know if the light was loud and if I would DEF NEED a blower?
The answer is that you have to figure out your own environment. I've set up two different spaces a few miles apart and they are VASTLY different. My recommendation to the guy who hasn't started is to get the light only first, turn it on in the room, monitor temps, add fans and ducting as you can afford and as you conceptualized how to duct them.
There are homemade equations out there that are supposed to help. They uses the cubic feet of the room (duh) and the light wattage to tell you the acceptable cfm's but they are rough estimates at best, and based on that person's experience in thier space. We all want to know what we need before we start cutting into our wallets and homes, but as far as I can tell, there is now way around it. You just have to trial and error it.
GreenFire - I FINALLY don't have to be at my house every 12 hours!! Check out how I did it on my journal. I live in a hot area as well, where - sorry Doctor D, but there is NO WAY one could keep a 400w tent closed with one small fan on the light that doesn't even pull
cool air from outside the tent through the light, but rather
hot air from inside the tent..? You really keep that thing under 80 with it shut?! I'm moving Northward!! Tonight!
GFK, I still havn't seen your setup in full, but the answer for us is exhausting the tent
and the light with as much cfm's as is affordable, and always pulling that air from outside the tent. Here's an idea: I remember you said you use your central air to keep temps down. If it's cool enough to live comfortably without it now, why not duct one AC vent - the one in the room you're using - into the light or the tent or both (for both use a Y connector duct). Then close all the other AC vents and turn it on like pretty low. I'm doing this at a friends apartment now.
You don't NEED two fans to exhaust both the tent and the light. You can use a Y connector duct for that, too. Just make sure it's a pretty strong fan. Two's prob better I'd guess.