Too much vs Too little light

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CBDgold01

Member
Pretty straight forward question.

Have a 20x36 inch (5 square feet) area & a 160 W QB. A small area on the sides won't really get adequate light.

Am I better off just running the QB or should add in a 130W (true watts) blurple that I have around?

I don't want to stress the plants with too much light in a little area, also don't want to give too little. The QB provides enough watts for 5sq ft but not enough spread.

I figure if I add in the blurple I will get better spread and coverage but will get a hot spot in the middle (tried this and plants in the middle started cupping, although not very badly).

Thoughts, too much or slightly too little? whats the verdict?
 
Kipn

Kipn

Well-Known Member
u will end up with half your grow room with good QB light and half with bad lighting plus you will find the blurple light will make your grow room hotter
 
D

devile

Member
35--50W/ SF will be needed for bloom, my marsproII320 led in tent 4x4, 46W/sf, my plants grow very happy
 
C

CBDgold01

Member
NanoGadget said:
Just my 2 cents here... i have a 135w HLG quantum board in a 2ft x 2ft space and it is more than enough. Last run that i used it to flower i pulled 5 zips off of 1 plant.
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What are your temps like? I sit at 70-71 lights on and 68 lights off.... I'm a little worries about getting fluffy buds from too low temps and no day/night difference
 
Rahz

Rahz

Well-Known Member
CBDgold01 said:
Thoughts, too much or slightly too little? whats the verdict?
Click to expand...
Guessing around 15 par watts per foot.

But the main problem is light spread. For the price of the blurple can you just buy a second quantum board? Run them in parallel. They would run half wattage, split the current and heat between two boards resulting in about 2 more par watts per foot for the same total wattage and would fit in your space right.
 
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NanoGadget

NanoGadget

Well-Known Member
CBDgold01 said:
What are your temps like? I sit at 70-71 lights on and 68 lights off.... I'm a little worries about getting fluffy buds from too low temps and no day/night difference
Click to expand...
I actually kind of encouraged my space to get warmer than i would normally run. I found that plants like a higher ambient temp with these lights because they lack the IR spectrum light to heat the plant mass at the canopy the way an hps would. I ran my extraction as low as i could while still maintaining odor control and i let my lung room get warmer than i would with an hps. I found that an ambient temp inside the grow space of 80 to 85 seemed optimal for lights on with the HLG QBs. Hope this helps.
 
Randomblame

Randomblame

Well-Known Member
CBDgold01 said:
Pretty straight forward question.

Have a 20x36 inch (5 square feet) area & a 160 W QB. A small area on the sides won't really get adequate light.

Am I better off just running the QB or should add in a 130W (true watts) blurple that I have around?

I don't want to stress the plants with too much light in a little area, also don't want to give too little. The QB provides enough watts for 5sq ft but not enough spread.

I figure if I add in the blurple I will get better spread and coverage but will get a hot spot in the middle (tried this and plants in the middle started cupping, although not very badly).

Thoughts, too much or slightly too little? whats the verdict?
Click to expand...
I would not worry too much.
Can I ask what happens when you add the 2nd blurple light and dimm the QB down a bit?
You can also hang the blurple fixture higher or both lights to lower intensity and heat stress. But even if you use only one QB and hang it a little higher for better coverage you should still get good results with such a small space. I've seen a lot growers using only 20-25w/sft. and they still got pretty good results and a pretty high gram/watt ratio.

You can also add a 2nd board to the exsisting driver. Simply connect them in parallel and the current will be splitted. Side effect, at half current you get ~5% better efficiency. I would finish this run with what you have available, save a few bucks in the meantime and get a 2nd board/slate combo and add it in parallel for the next run.
But I'm pretty sure you'll get around 200g also only with one board.
 
InTheValley

InTheValley

Well-Known Member
check out those little heaters, they are like $10 at walmart and are only 250watts, little things heat up a area pretty quick. Hook it up to an inkbird thermostat if you need to.
 
C

CBDgold01

Member
NanoGadget said:
Just my 2 cents here... i have a 135w HLG quantum board in a 2ft x 2ft space and it is more than enough. Last run that i used it to flower i pulled 5 zips off of 1 plant.
Click to expand...
NanoGadget said:
Just my 2 cents here... i have a 135w HLG quantum board in a 2ft x 2ft space and it is more than enough. Last run that i used it to flower i pulled 5 zips off of 1 plant.
Click to expand...
pan2707 said:
i was struggling with low temps also,
have put my extraction at bottom of tent with intake above blowing onto the boards got temps low 80s now and plant drinking much more and look healthier
Click to expand...
I would do this, but I have no ports at bottom of tent, only screen windows. I'm going to close them up and use a duct fan to blow warmer air from above downwards into the tent. Things look very healthy, but I want the buds to fill in and firm up well.
 
C

CBDgold01

Member
Rahz said:
Guessing around 15 par watts per foot.

But the main problem is light spread. For the price of the blurple can you just buy a second quantum board? Run them in parallel. They would run half wattage, split the current and heat between two boards resulting in about 2 more par watts per foot for the same total wattage and would fit in your space right.
Click to expand...
I already have the blurple around, would love another QB but it isnt really worth the money to me right now. Will do my best to solve the temp issue and finish this run and take it from there
 
C

CBDgold01

Member
Randomblame said:
I would not worry too much.
Can I ask what happens when you add the 2nd blurple light and dimm the QB down a bit?
You can also hang the blurple fixture higher or both lights to lower intensity and heat stress. But even if you use only one QB and hang it a little higher for better coverage you should still get good results with such a small space. I've seen a lot growers using only 20-25w/sft. and they still got pretty good results and a pretty high gram/watt ratio.

You can also add a 2nd board to the exsisting driver. Simply connect them in parallel and the current will be splitted. Side effect, at half current you get ~5% better efficiency. I would finish this run with what you have available, save a few bucks in the meantime and get a 2nd board/slate combo and add it in parallel for the next run.
But I'm pretty sure you'll get around 200g also only with one board.
Click to expand...
My QB actually goes up to 185 when its turned all the way up, although as of now I added in the blurple and dimmed the QB to what I estimate is around 150 watts
 
C

churchhaze

Well-Known Member
For 2-3 foot flowering plants after strech:

I'm thinking 10W/sqft is too low and 20W/sqft is too high. (PAR)

Best value between gpw and g/sqft is probably around 16W/sqft.
 
C

CBDgold01

Member
churchhaze said:
For 2-3 foot flowering plants after strech:

I'm thinking 10W/sqft is too low and 20W/sqft is too high. (PAR)

Best value between gpw and g/sqft is probably around 16W/sqft.
Click to expand...
I'm in week 4 flower, theyre only about 1.5 feet tall. flipped them with 4 weeks veg at like 6-7 inches tall
 
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