Is 400 watts overkill?

[tightpockt]

Is a 400watt ceramic metal halide overkill for a 24x18 inch cabinet? I know the more wattage the tighter the buds but by how much? I guess what I'm really asking is for opinions on weather the extra heat and power is really worth it giving my small space

 

[journey1111]

250w is more appropriate for that size. A 400w would be too hard to manage in that small of a space. The heat problem and power consumption is not worth a small possible gain in yield.

 

[BKCSG]

Is a 400watt ceramic metal halide overkill for a 24x18 inch cabinet? I know the more wattage the tighter the buds but by how much? I guess what I'm really asking is for opinions on weather the extra heat and power is really worth it giving my small space

Yes, it is overkill. It isn't the watts that makes the buds tight its the light intensity and lumens. Use a 250 w light and you will have very dense buds and will not have to worry about the heat killing your plants.. Also, with a 400w even if you get rid of the heat, it will eat up any humidity in the room, thus drying out your plants.

 

[la9]

If that's what you have, use it, you can't really have too much light, as long as you can keep the temps under control go with it. You can make a bigger cabinet if you have to, probably cheaper to redesign your cabinet than buying a smaller light. I try to use what I have, so that is my thinking on it.

 

[tightpockt]

Yes, it is overkill. It isn't the watts that makes the buds tight its the light intensity and lumens. Use a 250 w light and you will have very dense buds and will not have to worry about the heat killing your plants.. Also, with a 400w even if you get rid of the heat, it will eat up any humidity in the room, thus drying out your plants.

Thanks..I was trying to weigh the pros and cons and you put it in perspective for me. Right now I have about 200 watts worth of cfls for veging but I'm just gonna get a 250 cmh for the whole thing

 

[riddleme]

Glad to see some one going for CMH, not popular here yet though there are a few using them

as to your question 250 watt is fine for that grow area, your buds will be fine

and light is only one element in the growing process

a good grow (big dense buds) is the sum of all parts not just one

 

[cannabluntcies]

Not If you can vent the heat, but If you plan on using glass to insulate the plants from the bulb you would be defeating the purpose of using a MH over a HPS as most of the UV-B will be filtered by the glass. There is a special greenhouse glass that allows it to pass through however.

 

[Hayduke]

I use a 400 in 2'x3' and it is overkill. I now place veg plants outside of box and use ~3'x 3.5'...3x3 is probably perfect for a 400w imo.

 

[Hayduke]

Yes, it is overkill. It isn't the watts that makes the buds tight its the light intensity and lumens. Use a 250 w light and you will have very dense buds and will not have to worry about the heat killing your plants.. Also, with a 400w even if you get rid of the heat, it will eat up any humidity in the room, thus drying out your plants.

I did not see this before...but it is not true. Transpiring plants replace more moisture than the light will evaporate...this EXCESS humidity is pulled out of room with your exhaust.

IMO you will always want more light. If you are thinking 250...go 400...thinking 400...go 600 etc. You will not be sorry.

 

[sagensour]

If that's what you have, use it, you can't really have too much light, as long as you can keep the temps under control go with it. You can make a bigger cabinet if you have to, probably cheaper to redesign your cabinet than buying a smaller light. I try to use what I have, so that is my thinking on it.

It makes me sick when people say that "Theres never to much light". I find that to be a rookie statement. Have you ever heard of bleaching leaves? If so, thats from to much light!

There is a certain point on whats to much. The light may not be to much for the space, however its toomuch for the plants in that space. I would not recommend this. There is such thing as to much light. Spend the money on a Bad Boy T-5 and you wont go wrong!

 

[cannabluntcies]

What bleaches leaves? I always thought it was the UV radiation as it only does this under Metal halides in my experience. The HPS doesn't seem to do this.

 

[Hayduke]

My 400 hps in 2x3 even when closed up has never bleached leaves...it must be specific to MH, cuz I could not imagine creating more light than the sun

 

[sagensour]

I have a xtra 1000w HPS in a 2x4 breeding closet. Even 2 feet above the canopy I ended up with leaf bleaching. Thats useing a Cool Tube with Vortex and a HPS Hortilux. It happends more under HPS. Im certain of this. Research it.

 

[Bulldog73]

I am a firm believer in there is no such thing as to much light. Providing the heat and air circulation can be provided for. If you can control the temperature and humidity. If you can maintain great air circulation to optimize C02, then you don't have to much light. Just my 2 cents... Nothing more..