How many plants per 2800 umol of light

Those cob lights IMHO are decent. Drawing 600w from the wall you should get around 600 grams or close to it if you grow good. Be careful cause they will burn if to close. I would get a ppfd sensor. You cam get a good one for free in play store called "ppfd meter". Good luck!

If you haven’t purchased yet I highly recommend going for a quantum board set up.. much more efficient and like I said those par maps are highly suspect. Those phizilon lights are outdated and not very efficient. It’s also not 3000w from the wall. For a 2x4 or 2x2 I’d recommend a 200-240w quantum board like an SF2000 or TS2000, those will he plenty.

I’m very suspicious of that par map.. The numbers make no sense logically..

If you want "plenty of light" then aim for 35w-50w per sq ft. So, a 4ft x 2ft space is 8 sqft so if you have a total of 280w - 400w ACTUAL wattage, you should be golden. The Phlizon CREE COB that you linked is 600w ACTUAL wattage so that is plenty. To be honest, most manufacturers of good LED Lights and Quantum Boards price their products at per Actual Wattage of the light, e.g. a 200USD light should output 200 actual watts. Now, your light is 350USD for 600w so I would be VERY suspect of that light. Those diodes are probably not efficient and will cost you more in after a few months in extra electrical bills. If you want a good amount of light for your 2x4, I would recommend Viparspectra lights. Get either two XS1500 for 300 total wattage for 320USD, or two XS2000 for 480 total wattage for 374USD.

3000w is too much power that in long run I'd rather spend that money in better diodes having a better light quality for example buying samsung diodes instead of chineese ones. i'm using chineese diodes and doing good but you can't expect that 120$ light to give the results of a 400$ one, also it's not worth to me as in few months of electricity bills you'd afford it I'm not sure if Mandy Xiao is still working in Phlizon but if you can ask for her assistance she was very good and supporting with they lighting

best way to price out a light is determine its effencity per watt. its long term use cost analysis and spectrum. 3000W is a lot of juice in the long run... I operate off of 300w. www.youtube.com/c/MIGROLIGHT/videos This guy tests lights in a lab like settings and has good content. photo vs autos on par needed. www.youtube.com/watch side by side using cob lighting www.youtube.com/watch how he does all his measurements. www.youtube.com/watch I'd go for something other then a cob light. Good Luck.

I looked at those but the cobs put out 1000 umol of light more. There about 1800 umol and more expensive than the cobs that give 2800 umol. Watts is irrelevant if I'm right? Its all about the actual amount of light They emit. I'm new this is my first grow so correct me if I'm wrong.

3000w for 4ft2 I think is crazy, with 600-800w phlizon PH-B lights you should be more than ok how many plants depends on your growing technique: sog would be 36 plants in 7L pots or 49 in 3-5L pot... for scrog depending on veg time from 1 plant to 9-12 maybe? I'm personally using the PH-B10 in a 5x5 and it's perfect for me, for a 4x4 I would go with PH-8