250 watt hps vs 400 watt hps?

I am looking to buy a new light and i can't decide between a 250 watt hps or a 400 watt hps. The dimensions of my space are about 3.5 ft high, 2.5 feet wide and 2 feet deep. Which one should i get? and also what is the difference in heat output?

Well, if the heat can be controlled, the 400 will provide denser buds and a larger yield. However, it will also be overkill in that small space, as well as making much more heat than the 250. If you get a quality reflector, and have excellent reflection in the space itself, the 250 will be more than adequate. With all this in mind, a 250 in average hands provides for one daily smokers needs. A 400 can do more like three. Your spaces size limits realization of potential of a 400 w. You will get more, but you will get there with less efficiency.

250w HPS will be plenty for that box! You will def need a cooltube though.

i think 250 suits ur space much better, platnts will be constricted in suck a low area, the light needs to be like 20 in. away from the plants, as soon as u switch to the flowering they wont have any room to grow. do u have very good ventelation?

i agree
unless you plan on moving to a bigger grow area the 250 will be plenty in a space that small

My plan for ventilation is to get a reflector with 6 inch air cool openings and using a duct fan.

GTBuds420 said:

My plan for ventilation is to get a reflector with 6 inch air cool openings and using a duct fan.

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With only 3.5' of height you will need a cooltube. I dont think you can keep the light cool enough with an air cooled reflector.

You would need to keep the light too far away from the plants restricting how big your plants can be.

With a cooltube and a good fan you can keep the light much closer, not only allowing for more penetration of light, but for larger plants =]

Besides cooltubes are about the same cost as an air cooled reflector]

check out www.htgsupply.com

is an air cooled tube that much cooler than a air cooled reflector? also is a lumatek electronic ballast a good choice?

GTBuds420 said:

is an air cooled tube that much cooler than a air cooled reflector? also is a lumatek electronic ballast a good choice?

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They serve the same function.

Get the 250 for that space, but get the 400 if you think there is a possibility of an upgrade in grow space.

i use a 250w with a cheap wing type reflector and can easily keep the light 5" away with just a small fan blowing across the tops.