CMH Advice

Hi guys!

I am about to set up a 5x5 grow tent with 2x 315w CMH.
As a budget option the guy at my local grow shop suggested that i buy 2 kits that include a remote ballast, a bulb and a "stucco" reflector.

Do you guys think that these reflectors often used for HPS will work as well with CMH?
I haven't seen any complete CMH kit with this kind of reflector.

Any advice will be appreciated!

assulin said:

As a budget option the guy at my local grow shop suggested that i buy 2 kits that include a remote ballast, a bulb and a "stucco" reflector.

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Not sure what a "stucco" reflector is. You mean something like a bat wing? He was suggesting it as a budget option, so I would suspect that means serviceable but not optimal.

Here's where I got mine. Probably cheaper than the hydro shop. You might want 3 or even 4 if you can handle the heat. You could do 2, but that's a little underpowered for a 5x5.

For a 5x5 just get one good DE 1000 watt CMH and call it a day. Gonna have to keep the plants on the shorter side.

Thanks for the replies!
From what i've researched, 5x5 is the go to size for 630w CMH.
And heat is a problem here right now as well!


this is the one im referring to. Thoughts?

assulin said:

From what i've researched, 5x5 is the go to size for 630w CMH.

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Maybe in veg, not in flower.

assulin said:

this is the one im referring to. Thoughts?

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Well it's a cheap reflector but it reflects. You could always upgrade that later. As @PadawanWarrior mentioned you need more watts for a 5x5. Thats gonna bring heat. A good LED could mitigate that.

I would hang an HLG 650r in there and call it lit.

Renfro said:

I would hang an HLG 650r in there and call it lit.

HLG 650R

High Efficiency Commercial Indoor Horticulture LED grow light designed to replace a double-ended 1000watt HID with just 6100 Watts. 1700 PPF @ 2.8PPF/W. Full-spectrum. LED Module made by Samsung. Powered by Samsung LM301H LED and Deep Red LED 660nm

horticulturelightinggroup.com

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Drool, lol.

And $110 off with the coupon code "RIU10".

If you're only going to use 2 lights you could make your canopy 4x4 and have a little room to move around.

If you want to use all of the 5x5 then 3 of the 315's would be better. I would also recommend a better reflector if you can afford it.

I get lots of weed (12 oz last grow) in My 4x4 box with one 315 cmh. Two will cover it nice as long as you turn your plants a bit. You wouldn't be able to cover well with a screen. Maybe 4x5. I'm just saying. It might even work much better with the overlapping effect. IDK. Shoot for 24+ oz and your doing well.

5 feet out from a single light might be a bit though. They are set at 26 inches from the tops.