If you just put a piece of glass on the bottom of your light fixture and rigged some vents to pull air into it and exhaust the hot air outside, it would make a big difference. With those HID bulbs you want your canopy temp to run around 77 F or 25 C. That’s a lot cheaper then replacing them with LEDs, and with the same amount of light output you would still have to exhaust some hot air.
Unless something has changed with the cmh tech, they didn’t like being air cooled at all. The air cooled models cooled the hood itself and had no direct moving air over the bulbs. They were very prone to explode from that. Being said, latest and greatest may be different.
I think most of the CMH bulbs now sold have a double glass jacket just to prevent cooling and temperature shock of the arc chamber. The gas discharge arc of these tubes typically is inside a 1 inch long tube that is about 1 inch in diameter. The outer glass bulb is the insulator that keeps the inner tube from shattering from temperature shock. I searched for “cmh hid bulb air cooled” and found several nice looking fixtures with exhaust ducts in line with the bulb(s). Since the grow chamber air should be a constant 77 F, instead of 20-100 F as in outdoor fixtures, I don’t think there is much danger of shattering.
That said, a CMH explosion is pretty dramatic. Some growers include an automatic fire extinguisher to prevent setting the house on fire! I think I’ll stick to nice safe LEDs, running in series constant current mode.
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Having seen one in person, I concur. I would definitely double check my equipment is rated for such use before doing a makeshift cooling setup.
I don’t have a lot of room. So I’m Starting a gorilla tent 2’ x2.5" x 7" with 2 plants. I want to go with LED light. What Plug Wats do I need?
You’d need 250 true watts. But 2 plants will get a bit crowded in there.
Thank you much.
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You can get away with less with higher end lights. Like 175 watts. Which with that small of a space you could probably do at a decent price. Let people know when you start shopping and @dbrn32 or someone can help give you options that fit whatever budget you have.
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What is draw power of your led? 300W? If it is so, it can work for bloom stage.
I am using MarsII 1600 led in tent 4x4, 40W/SF, I think 35–50W/sf can work for bloom
A small led MarII400 can work for you, it is an old brand in the market for 10 years and they have warehouse and repair center in many countries: https://www.mars-hydro.com/led-grow-light/mars-ii-led-grow-light/buy-mars-ii-400-led-full-spectrum-hydroponic-led-grow-light-mars-hydro-for-sale
Why do you keep posting about Mars? You seem to be an employee or something of theirs?
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This one looks good to me,
https://www.amazon.com/dp/B01MAZ1C2S/?coliid=I1O5P336522W7S&colid=1Q2VUWSJ9D9L8&th=1
ill never use blurple lights again
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I can’t count the number of deceptive statements made under the specs section of that light on Amazon. I recommend you look for a 600w light from Mars, Roleandro, or any light vendor that the specs show actual draw to be 300 watts. On most of these lights, 40 watts is used for cooling. You will still be getting a 260 watt light @Azmov.
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