proper light

[mactight]

I have three ladys laying under a 400 hps in a room 36''x28''x88'',wraped in metalic wrap paper,is that enough light(lumens) for these ladys?And if yes could i place another one in there?Thanks for all the help:woohoo:

 

[BudManDan]

Ive always grown in a space slightly bigger than that (not as tall though!) with a 400w HPS, works great, enough light for the buds to grow big, not too mich heat to cause problems. I think if you get another in there you may run into heat troubles, whats your ventialtion like?

 

[mactight]

Very nice set up.It si 79-84 degs with the light on and 70-73 when the light is off.

 

[Kupunakane]

I did a bit of researching, and found that if you are well prepared for it you can do ok with a 400 watt, but a 600 watt will throw 95,000 Lumens as compared to about 54,000 Lumens for the 400. Light is every thing.
smoke in peace
KingKahuuna

 

[mactight]

I have read on here acouple of times that there is a formula to find out if you have enough lumens for your grow space,I cant find it in a search.Does any one know the formula for that?

 

[booradley]

5000 lumnes per square foot...

 

[mactight]

5000 lumnes per square foot...

How do you caculte it to find out if I got enough?whats the forumla on that?

 

[Hick]

36''x28''x88''

.....3'x2.25'=7.5 sq ft
7.5 sq.ft x 5000 lu.=37500 to fill the space..you're right on the money...w/the 400 "IMHO"

 

[jamstein]

more lights supposed to always give you more yield, but the 600 watt HPS lamp AND ballast put out so much heat your ventilation will run into trouble

 

[booradley]

more lights supposed to always give you more yield, but the 600 watt HPS lamp AND ballast put out so much heat your ventilation will run into trouble

From what I've read on here that's true to a point but plants can only use so much light. After that, you're just burning them. I don't know the max lumens MJ absorbs (or whatever measurement you would use).