Light burn with LEDs

This is my first grow using LED lighting in my 3'x2' space and I noticed my light is starting to burn the tips of the leaves that are directly under the center of the light. I raised the light all the way up (about 24 inches), and still noticing some slight burning. Vertical space is going to be an issue, because I still have about 7 weeks to go. I had no problem until I turned the bloom switch on, which increased the wattage from 175 to 275 on my Viparspectra PAR 600.

Which is my best option?

1) Turn off the veg switch and only run the bloom (red) lights in flower (reduced wattage)?

2) Get 2 300w lights and spread out the intensity?

3) Downgrade to a single 450w, or 300w?

Have you fed any nutes yet? Do you have any air circulating? Alot of factors that come into play here. More info will get you a better answer.

Pictures?

Surf Bandit said:

This is my first grow using LED lighting in my 3'x2' space and I noticed my light is starting to burn the tips of the leaves that are directly under the center of the light. I raised the light all the way up (about 24 inches), and still noticing some slight burning. Vertical space is going to be an issue, because I still have about 7 weeks to go. I had no problem until I turned the bloom switch on, which increased the wattage from 175 to 275 on my Viparspectra PAR 600.

Which is my best option?

1) Turn off the veg switch and only run the bloom (red) lights in flower (reduced wattage)?

2) Get 2 300w lights and spread out the intensity?

3) Downgrade to a single 450w, or 300w?

Click to expand...

OP that model has a pretty hot center on their PAR map, if it was less than 18" away before you raised, light burn as you describe is certainly possible. Def want as much as possible so both switches, but yeah 24" minimum. You could see what happens. Don't downgrade to a smaller single unit, but yes two 300w would allow for more even coverage without the hotspot. You're on track just need to decide..

@Surf Bandit

bro can you add pics? Also how is that light performing in Veg? looking to pick up 3 or 4 of the 300 watt

Cheers

Air circulation is optimal - two fans and constant fresh air pulled in passively from the inline exhaust fan.
I don't think nutrients are causing it, I'm feeding organic nutrients every other watering, half strength, and plants seem happy.

The reason I believe it's light burn is because the center colas had "tacoing" leaves very bad at 16'', then I raised it to 22'' and they went back to normal. I still noticed some brown tips, so I raised it all the way up to 24'' and saw additional improvement. Now, only a couple tips are brown. But as they grow taller, I'm going to have this issue again, so need to do something with the light going forward.

@boston Puff - I like the light, but as noted in this thread the center has a pretty intense hot spot. I've used HPS for years, and this is my first LED. I was skeptical at first, but the plants are happy! I'm consuming much less electricity with LED, it pays for itself in about 5 months. Also, now I don't need another fan for intake or a duct fan to cool the hood. The tent stays at 73 degrees with my exhaust fan at 1/2 power and a passive intake.

I got the Viparspectra PAR 600, which is their newer line of lights. The older versions are half the price on amazon, so I'm going to return this one and try 2 300's to spread out the intensity. They guarantee their product for 30 days, so I'm going to send it back for a full refund.

Are you comfortable working with electrical at all? This best grow light for small grows are going to be a DIY COB build.
Definitely need to understand AC/DC theory and know/learn to solder.

I have 320watts of cree LED in my 3×3 closet. You could put the LEDs 3inchs from the canopy I bet with my setup

Surf Bandit said:

Air circulation is optimal - two fans and constant fresh air pulled in passively from the inline exhaust fan.
I don't think nutrients are causing it, I'm feeding organic nutrients every other watering, half strength, and plants seem happy.

The reason I believe it's light burn is because the center colas had "tacoing" leaves very bad at 16'', then I raised it to 22'' and they went back to normal. I still noticed some brown tips, so I raised it all the way up to 24'' and saw additional improvement. Now, only a couple tips are brown. But as they grow taller, I'm going to have this issue again, so need to do something with the light going forward.

Click to expand...

Honestly, it looks more like mild nute burn than light burn. Here is an example of light burn:


All those white spots in the margin appeared about 6 hours after increasing the light intensity on my COB lights.