so what you are saying is that for COBs/LEDs you need a 25w LED output per sqft to be optimal. when I mentioned 2 sqft, I really meant 2 foot square area (2 foot x 2 foot) which would be one COB per 4 sqft which was 8 COBs total, my bad... and yeah, doesn't seem like 8 COBs would do the trick.
On a different angle: how many COBs do you think would be needed for a single plant, I was thinking 4 per plant max. Because of state laws, I'm only allowed 12 plants total which means I will never have a "full" bloom tent and a "full" veg tent at the same time. So, I was thinking of only having 4 to 6 plants at a time in the bloom tent which would lead to 16 to 24 on these lights. It's still very expensive but I could add 4 COBs at a time slowly.
I'm still wondering what the benefits of COBs over just two 630 cmh fixtures are seeing that you believe that two 630 cmh fixtures would do the trick nicely at a total cost of $1200. Is it that COBs are more efficient? last longer? better spectrum? ...
Thanks