chamenon
Member
I've scored some hyper tough shop LEDs. 45w at $8 a piece, 180 w in total. I'm planning to use one of these for the mother plant and use the remaining 3 for vegetating and flowering 3 clones cut from the mother. For this I was planning to buy a proper full spectrum grow light and use 2-3 of these shop lights as side corner supplemental lights.
But looking at grow lights, they are practically a combination of 2700K-5000K white LEDs and some red LEDs around 660nm with some blue LEDs. So I'm thinking since I've bunch of 5000K LEDs already, what if I add a 20-40w blurple in order to just enhance my 5000K lights' spectrum for flowering?
I'm aware that a proper grow light is more convenient but my starting costs for my grow tent is starting to add up and I'm trying to utilize what I've on hand for now and get the most amount of PAR for the money with the equipment on hand.
Looking at the distribution of light spectrum in various lights here is my calculation to justify my logic;
According to the chart I'm sharing below my white 5000K LEDs produces
0.8 part InfraR, 41 parts Red, 45 parts Green, 14 parts Blue, 0.15 parts UV
and a Blurple LED produces
1.4 IR, 75 R, 25 B an 0 UV,
therefore if I combine 135 watts of 5000K and 20w of Blurple, I should get a 155w LED with these ratios;
0.8 IR, 45 R, 39 G, 15 B, 0.13 UV which seems to an acceptable balance of RGB compared to Sun, HPS and other options like white and red lights.
Here is how I calculated;
1. Multiply the spectrum values of the 135-watt light by 135:
0.88 IR, 45.39 R, 39.19 G, 15.42 B, and 0.13 UV.
I can also add another 20w Blurple to have 175 watts at the following light ratios;
0.94 IR, 48.77 R, 34.71 G, 16.51 B, and 0.12 UV.
This assumes 20w Blurple will produce equal amounts of red and blue (but I primarely care about the RED part since 5000K LED should have enough blue in it already)
So my question is; are my assumptions wrong? Am I missing anything in this comparison? (One thing that I'd be missing is 2700K LEDs but I think the amount of red LEDs in the blurple light should make up for the lack of them, also I can always throw a 30w 2700K LED in there for $6 if needed)
These are the blurples I'm considering;
Sure, I can get a UNIT FARM grow light for a little bit more at $30 but this won't give me enough REDs, I would be just buying more white light with the grow light tax added.
To reiterate my point, I'm not trying to have a blurple grow setup, I understand why they are not optimum, I'm just trying to enhance my 5000K for flowering with the addition of some blurple lights for spectrum coverage.
Looking forward for inputs, suggestions, and inevitable roasting for wanting to use Great Value grow lights.
Also looking for any other blurple LED recommendations.
Or is this a terrible plan and should I bite the bullet and get a 100-150w ViparSpectra and try to save money somewhere else?
But looking at grow lights, they are practically a combination of 2700K-5000K white LEDs and some red LEDs around 660nm with some blue LEDs. So I'm thinking since I've bunch of 5000K LEDs already, what if I add a 20-40w blurple in order to just enhance my 5000K lights' spectrum for flowering?
I'm aware that a proper grow light is more convenient but my starting costs for my grow tent is starting to add up and I'm trying to utilize what I've on hand for now and get the most amount of PAR for the money with the equipment on hand.
Looking at the distribution of light spectrum in various lights here is my calculation to justify my logic;
According to the chart I'm sharing below my white 5000K LEDs produces
0.8 part InfraR, 41 parts Red, 45 parts Green, 14 parts Blue, 0.15 parts UV
and a Blurple LED produces
1.4 IR, 75 R, 25 B an 0 UV,
therefore if I combine 135 watts of 5000K and 20w of Blurple, I should get a 155w LED with these ratios;
0.8 IR, 45 R, 39 G, 15 B, 0.13 UV which seems to an acceptable balance of RGB compared to Sun, HPS and other options like white and red lights.
Here is how I calculated;
1. Multiply the spectrum values of the 135-watt light by 135:
- InfraRed (IR): 0.8 * 135 = 108
- Red (R): 41 * 135 = 5535
- Green (G): 45 * 135 = 6075
- Blue (B): 14 * 135 = 1890
- UltraViolet (UV): 0.15 * 135 = 20.25
- InfraRed (IR): 1.4 * 20 = 28
- Red (R): 75 * 20 = 1500
- Green (G): 0 * 20 = 0
- Blue (B): 25 * 20 = 500
- UltraViolet (UV): 0 * 20 = 0
- InfraRed (IR): 108 + 28 = 136
- Red (R): 5535 + 1500 = 7035
- Green (G): 6075 + 0 = 6075
- Blue (B): 1890 + 500 = 2390
- UltraViolet (UV): 20.25 + 0 = 20.25
- InfraRed (IR): 136 / 155 = 0.88
- Red (R): 7035 / 155 = 45.39
- Green (G): 6075 / 155 = 39.19
- Blue (B): 2390 / 155 = 15.42
- UltraViolet (UV): 20.25 / 155 = 0.13
0.88 IR, 45.39 R, 39.19 G, 15.42 B, and 0.13 UV.
I can also add another 20w Blurple to have 175 watts at the following light ratios;
0.94 IR, 48.77 R, 34.71 G, 16.51 B, and 0.12 UV.
This assumes 20w Blurple will produce equal amounts of red and blue (but I primarely care about the RED part since 5000K LED should have enough blue in it already)
So my question is; are my assumptions wrong? Am I missing anything in this comparison? (One thing that I'd be missing is 2700K LEDs but I think the amount of red LEDs in the blurple light should make up for the lack of them, also I can always throw a 30w 2700K LED in there for $6 if needed)
These are the blurples I'm considering;
Great Value 2ft Selectable Spectrum LED Grow Light, 20W, Linkable - Walmart.com
Buy Great Value 2ft Selectable Spectrum LED Grow Light, 20W, Linkable at Walmart.com
www.walmart.com
Sure, I can get a UNIT FARM grow light for a little bit more at $30 but this won't give me enough REDs, I would be just buying more white light with the grow light tax added.
To reiterate my point, I'm not trying to have a blurple grow setup, I understand why they are not optimum, I'm just trying to enhance my 5000K for flowering with the addition of some blurple lights for spectrum coverage.
Looking forward for inputs, suggestions, and inevitable roasting for wanting to use Great Value grow lights.
Also looking for any other blurple LED recommendations.Or is this a terrible plan and should I bite the bullet and get a 100-150w ViparSpectra and try to save money somewhere else?
Last edited:
