800w Grow Light in 2x2x5' Grow Space.

[shane369]

Hi everyone! It's my first time growing my own cannabis, as of now I'm using a BESTVA 800W dual chip LED grow light in a 2' x 2' x 5' grow space. I'm worrying that the light's too much for my plants. For my very first grow, I fitted 3 plants in my grow box, of which are 2 Royal Dwarf Autos, 10 days old and a 7 days old, and a landrace form my country, 13 days old. I started it on a 16/8 light schedule but recently changed it to 18/6 because I've read online that 18/6 is best for autoflowers. The temperature fluctuates around 27 - 33 degrees celcius and the humidity is from 38 - 70%, it depends on the room temperature outside the grow box. Do you guys think 800w is just right?

[DrPhoton]

It should be fine for that size, could even take a little more light. It only draws 150 watts which provides roughly 500umols of photon density averaged over 4 squares. Which the optimal light levels are around 700umol, with maximum of 1000umol.

So as previously said, should be no problem. Just use the manufacturers recomended fixture height.

[furrysparkle]

For a 600w hps producing 1100 umol/s will I need to worry about CO2 levels or will fresh air exchange be enough?

[DrPhoton]

If its for a 4x4 space, then co2 supplementation is not required. Fresh air will be enough. With more powerful light sources or using that light source in a smaller grow area, then co2 supplementation will start becoming a requirement.

[shane369]

Great! Thanks DrPhoton.

[shane369]

It turned out that my grow light's too much for my seedlings! My seedlings are showing light burn symptoms and they grow very slow, they are probably stunned What can I do about this? As of now I placed the grow light furthest possible almost touching the ceiling. And I covered some of the LEDs with cloth. Will this work? I'm really worried

[shane369]

I am now using my two spare 15w grow light bulbs and a 5 meter RGB LED strip that I set on blue on my seedlings. I placed the bulbs around 7cm away from the seedling. I hope this works DrPhoton! Thanks for the advise!

[DrPhoton]

I think it will work out fine, just be careful with the light. It does take time to work out fixture heights, especially without a light meter.

[shane369]

Is CFL better?

[furrysparkle]

shane369 cfls are only better in a stealth setting, for less electricity and probably a lower initial investment you can get a small HID or an LED that fits your needs better

even for seedlings I would recommend an inexpensive LED growlight even a 9w will be good for seedlings

[furrysparkle]

Just edited

[shane369]

Ohh thanks furrysparkle

[DrPhoton]

I also use LEDs for germination and cloning for up to 14-21 days. They are 19w philips bulbs. You do have to have them further from the plants compared to CFL. I have mine around 12 inches from the light, but this distance will vary from the different wattage and bulb types.