First Project Questions

[anon0988]

I have a few friends that are going to be setting up a small first time grow. They've decided to keep it small at first and we've built a structure inside a closet. It's dimension are 4'w x 2'd x 6'h. I'm the handyman for this project as they don't have much in the way of technical skills. Before I get into finalizing the project and making the major purchases, I figured I'd seek the knowledge of this community. I had an initial concept for how everything would work, but after discovering this site and reading a bunch of threads I've changed some aspects and have some questions about others.

For lighting I was going to go with an iPower 400w MH/HPS setup. The inside of the box is going to be covered in Mylar to increase the reflectivity. The cheapest way I found to get it was to buy the 'emergency blankets' made of Mylar, found here.

If you look at the diagram I've attached, can anyone make a recommendation for what CFM rated exhaust fan I'm going to have to have, and any pointers on the air filter would be nice. Please note that the cool tube is 6", so I'll be using 6" hoses, filter, and exhaust.

 

[skaarup]

400watt

400watt

400 watt is way way too much and way too big.

go for 150 at the most hps

 

[skaarup]

I did some 250 watt for a areal like yours... that was way too much light I mean first time you see it, you have no idea how much light and heat they give

 

[anon0988]

From what I've read, you want to get about 50w/Sq ft. This setup would give 50w/ft exactly (400w bulb, 8 square feet of floor space). If I'm wrong that's fine, but I've seen the 50w/ft rule in several places. If you think this is too much could you point me in the direction of where you found your material?

 

[messn'n'gommin']

I use 2 250's in a 2'x4'x8' closet, covering an area of about 7 sq ft. A 603cfm on a voltage regulator set at about 60%. Internal temps about 75F-80F and ambient about 65F-70F. Air intake port area about 3 times the exhaust port, but a two to one ratio is about the ideal. I forget the numbers, but, here is a good thread to absorb:

“Ventilation 101,” by redgreenry
https://www.icmag.com/ic/showthread.php?t=112862

The 50w/sq ft is usually meant as a minimum for HID. Approaching 100w/sq ft is getting to be too much. So, shooting for about 65w-80w should be about ideal light coverage. As long as your ventilation system is adequate, you should have no problems, even with a 600w.

hth