315 CMH in a 2 x 2 tent

[NewToTHC]

Hello:

I understand CMH bulbs run much cooler than a HPS or MH but curious if heat would be a issue in small 2 x 2 tent. Would be using a 4" fan for ventilation. I have used a 250watt MH before and the heat was difficult to manage in the summer months so not sure if I am wasting my time on trying a CMH. Could move the ballast external to the temp to help. I do want to upgrade my budget LED, so debating spending more money on a good LED, or try a 315 CMH.

 

[013]

wattage is wattage and the conversion of electricity to light is always gonna generate heat. I’ve ran one in 4X4 but not 2X2, better have hygrometer to monitor temps and hopefully digital ballast so you can dial her down. Set it up and monitor temp & rh is only thing I know to say.

Buy the LED, it will cost a few pennies now but save on power efficiency later. I started with T5, then 315 cmh, next 600 hps, finally 2 Mars lights. You should skip a few steps there

 

[NewToTHC]

Not overly concerned about power usage efficiency (~ 11 cents a kilowatt here). Was thinking of only growing during the fall to spring and running the lighting cycle at night. The heat difference between the LED and CMH can compensate for additional heating in the winter months required in the room. But you are right, really won't know until I try it.

I can get started with a 315 CMH kit (ballast, reflector etc) without bulb for under $200.00, add a good bulb for another $100.00 and I am still probably just over 1/2 that a high quality LED setup is going to cost me north of the border.

 

[nivek]

i just bot and installed a 630w cmh,, for a 3 x 4' area. plants love it seemingly

resist the urge to feel you 'need' to go led,, you don't

research told me that a 315 was good for 6 sq ft for flower,, so barely over your specs,,

my driver, which i have outside the flower space, is dimmable, 3 dif selections.

i use the heat in the winter as my grow room is in an outdoor studio space

i bot it basically because knowlegable folks whose opinions i trust, in this site, convinced me to do so, and i also wanted to try something new,,

and, btw,, i also own/use 4 led lights as well

oh sheesh,, i guess i gotta call this one a 'ballast',, not a driver,, ha

 

[NewToTHC]

i just bot and installed a 630w cmh,, for a 3 x 4' area. plants love it seemingly

resist the urge to feel you 'need' to go led,, you don't

research told me that a 315 was good for 6 sq ft for flower,, so barely over your specs,,

my driver, which i have outside the flower space, is dimmable, 3 dif selections.

i use the heat in the winter as my grow room is in an outdoor studio space

i bot it basically because knowlegable folks whose opinions i trust, in this site, convinced me to do so, and i also wanted to try something new,,

and, btw,, i also own/use 4 led lights as well

oh sheesh,, i guess i gotta call this one a 'ballast',, not a driver,, ha

Well...I am on my 3rd LED, first two were blurples and frankly useless, my current is a Spider Farm Sf1000. Like it and does me well in my current 12" x 15" little cabinet box. Have a 2 x 2 tent on the way and although my yield needs are not great, I would like to kept 2 to 3 small plants going for variety .So saying that will need to upgrade my current setup.

I did think about adding a second Spider Farm, but for a little more can go with a no frills 315MH. As I referenced heat could be a issue, but my tent will be in a enclosed balcony that I keep with tropical plants. Having the heat pumped out into the balcony would certainly save on heating costs in the winter, beginning to lean to the CMH, or at least try it.

Could always keep the Spider Farmer for veg, if it takes double the time no big deal for me. I get that LED's can be more efficient over the long run, but we would be talking years, and years, and who doesn't like the latest and greatest and buying a new LED fixture every two years anyways is going to throw that out the window.

I haven't seen any dimmable ballasts for CMH?

 

[NewToTHC]

All things considered if one matched a LED fixture to a CMH so they both produced the same PPFD would it be fair to say the CMH would provide better results in terms of bud quality, terpenes etc due to the UV and more encompassing spectrum provided?

 

[423]

Ive used a 315 cmh in a small closet. It measured somthing like 20"×40.
Id be concerned with space and heat.

I can use the cmh in the winter, but becouse of heat not in the summer.
If you had a remote ballast outside of the tent and lots of cool air coming through it'd help.

A remote ballast, or remote driver helps a lot reducing heat in a small place.