Lights for beginners

I’m using a 2ft wide x 4ft long 5ft high grow tent with exhaust. what watt light should I use i been using a 600watt mh but having problems with the temp been running 80 to 86 Fahrenheit I have a dimmable ballast should I just turn it down

Air cooled hood would be an option, 2-250 watt hid’s, 1-315 cmh, or a number of led options would all do well in that space and probably run a little lower canopy temps.


Led’s can work but they can be misleading for what is labled and what they actually are for someone who has never dealt with them. I will be trying out a cmh for my next light purchase, but there’s no better place to seek answers about or to take a look at what everyone uses and base it off your grow space. 50w/sqft is the number you want to shoot for, I believe so anyway.

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You can make that 600 watt bulb work. You just need a “cool tube” that surrounds the bulb and then you duct the exhaust fan to the tube. That way most of the heat goes out the exhaust. Obviously, the exhaust should not go right back into the tent. Maybe you can send it out through a window? Or add a duct into another room, so the incoming air is cool.


Im in sw & use mh. With a cool tube youll have no problem with heat


Anyway you could send me a pic of venting to exhaust? Do you T it?

I don’t use HID bulbs. But I do vent exhaust air through my LED heat sinks. I think you can see my whole setup on the Blue Dream Grow Journal. I use 4 inch flexible ducts from home depot and I use a custom made rigid Y duct to connect two of the four inch flex ducts into one six inch flex duct. But after I made it, I saw just the part I needed at a local hydroponics shop.

If you do use flex duct, you need to screw all the parts together, THEN use duct tape to seal it. Don’t just count on duct tape to hold it together: It won’t and when your air flow fails that can be very expensive.