Not bleaching even at 5 inches?! (viparspectra 450W)

Hi all, I'm a little concerned about my light.


It's a Viparspectra 450w new this winter and I just tested it and it's drawing 206watts exactly as it did on day one and as rated with both switches on for full light so it's drawing the correct amount of power.



It's in a small tent and I've been progressively moving it down from the manufacturer recommended minimum distance of 18 to 24 inches for flowering as I currently have one plant so I can really concentrate it down lower.


However no matter how close I've moved it to date I see no signs of bleaching. (This is on a sativa cross BangiHaze and Panama plant with fine leaves if it matters)


I fertilize just adequately and keep my plants at a fairly light to medium green, not super dark green so not sure if that affects things are not.


I had it at exactly 5 inches from the bottom of the light to the top of the top buds for 3 days with no bleaching at all and just lowered it again to 4 inches and will check again tomorrow.


I'm not *trying* to bleach it but I'm trying to get a sense of the limits and this seems a bit odd.


Could this be because they spread it out over so many led's that no one led is too bright? My old LED had fewer lights and though it was lower wattage it definitely would burn if too close.

Is the same with all their lights,i have a 300w laying around somewhere and buds could get to almost touching the unit and would be no signs of bleaching

Weird, after I posted this I ran it at 4 inches for a few days, also no bleaching. I wonder if anyone has tested these with a light meter to confirm the specs they are supposed to be at?

I had a much different experience. Using a Viparspectra 450, when I brought the lights down to about 10 inches, I basically ruined a whole crop. Too much light can kill your plants. 18 inches is the minimum height I would use for flowering personally*.


*Using Viparspectra 450.

I have 2x viparspectra 400 in my veg tent and I couldn't remember seeing bleaching, but I just went back through my pictures and I have a shot of a plant that grew so tall it actually touched the lamp and it started to bleach/burn in those spots. I'm not sure if it is light bleaching or heat bleaching though to be honest. And it only happened seems to be where it was in direct contact with the light.

de145 said:

Hi all, I'm a little concerned about my light.

It's a Viparspectra 450w new this winter and I just tested it and it's drawing 206watts exactly as it did on day one and as rated with both switches on for full light so it's drawing the correct amount of power.

It's in a small tent and I've been progressively moving it down from the manufacturer recommended minimum distance of 18 to 24 inches for flowering as I currently have one plant so I can really concentrate it down lower.

However no matter how close I've moved it to date I see no signs of bleaching. (This is on a sativa cross BangiHaze and Panama plant with fine leaves if it matters)

I fertilize just adequately and keep my plants at a fairly light to medium green, not super dark green so not sure if that affects things are not.

I had it at exactly 5 inches from the bottom of the light to the top of the top buds for 3 days with no bleaching at all and just lowered it again to 4 inches and will check again tomorrow.

I'm not *trying* to bleach it but I'm trying to get a sense of the limits and this seems a bit odd.

Could this be because they spread it out over so many led's that no one led is too bright? My old LED had fewer lights and though it was lower wattage it definitely would burn if too close.

Click to expand...

Without the size of your tent, your post is really insignificant! What are you making comparisons with?

What was your PAR reading at that height? I bet you at 5" you could feel the heat on the back of your hand.

Keeping your light below 1000 PPFD will solve issues but, anything over 1000, you need to suplement with CO2. So, what is your reading?