250hps Vs 400w?

[UrbanCultivator]

Hi guys,

 

I'm growing in a relatively small area, a clone tent with the dimensions of 0.8x45x0.8 and am ready to purchase a hps bulb and ballast for flowering. I already have a cool tube + ducting for the fixture. I am just wondering which would be best in this area of space between 250w and 400w hps and if anyone has any info or experience in regard to this. Much Appreciated.

 

UC

[UrbanCultivator]

Forgot to add that will probably be growing 3 trained females max under the light and in the space I have to use.

[TheTreeBoundRat]

Welcome too OS mate. I cant help but someone or nufan will be in shortly. Good choice using the hps over inefficient cfls. Good luck

[Budgiekk]

hey mate ,

mines 1m x 1m x 2m high and i got a 400 watter working a treat, no cooltube though so you should have even better temps

 

i assume your dimensions are in metres ? (0.8) how high is it 45 ?

 

budgie

[UrbanCultivator]

Thanks a lot RiverRat, much appreciated!

 

Budgie sounds good mate, yeah in meters mate so 80cm tall and wide and 45 cm deep. Just wanted to make sure 400w wouldnt be an overkill or not necessary in that small space, also heat wise. Up till now its just been high output CFL's 130w. But obviously does not have the intensity or penetration needed for optimum flowering.

[Reverend]

Have a look here:-

 

https://cannabis.community.forums.ozstoners...rs/lighting.php

[UrbanCultivator]

Thanks a lot for that Gills! Very nifty. So it recommends 234 w so I'm guessing 250w max!

[smokinjoe]

Your ladies will appreciate the extra lumens of the 400w. Since you have the cool tube neither should impact temps significantly.

 

The two qualifying criteria will both related to the depth of your pocket and length of your arm.

 

Can you afford the 400w and the additional power it will consume.

 

I'd go the 400 incase at some point down the track you are growing in a different space.

[iatd]

Hey UrbanCultivator.

 

Your grow tent is 2.62 ft x 1.47 ft. = 3.85 sq ft.

 

Your min lumens (in flower) per square foot is 5000.

 

A 400w HPS puts out about 50k lumens.

 

So 50000 / 3.85 = 12987

 

So Thats a lot more then you need. But that just means bigger buds

 

Also i would look at using MH for veg and HPS for bud. The MJ needs different light spectrum's during each period to grow at its peak.

 

My 2 cents.

Edited January 9, 2010 by iatd

[iatd]

Sorry forgot to say something.

 

You don't need to buy a new ballast if you want to run a MH. You can buy a Conversion Bulb which will allow you to get MH light from a HPS Ballast. Hooray for technology.