LED Grow Light Forum

Hello, nice to meet you, my name is PurpleGlowGrow and I will be participating in the CLW GFP. I have just received my light, set up my tent and am ready to start planting. This light is quite bright for only operating at 230 W in veg mode and seems to be covering the 16 ft^2 area very well (10 W less than a 4 bulb t5 unit that would be used for vegetative growth in an 8ft^2 area). I've got more work to do for now, so I'll check back in at the end of the week with more detailed information about what I will be using and growing for the next 90 days.

Welcome to the forums!

230w in 16 sqft is a little light, imho, you'd be better off in the 8 sqft area (assuming a reasonable shape) if you want better growth than you had with fluorescent lights.


SME

First, let me apologize for only getting back to this now. I have had a lot to do for the last two weeks and do not expect to have any more gaps like that in the future.

Secondly, after two weeks of using the light for vegetative growth, SME, I 100% agree with you. This is contrary to the manufacturers' (CLW) claim of being able to cover a 5x5 area with the light that I have. I was not using the entire 4x4 area, but plants to the outside of the 3x3 area are suffering from inadequate lighting. I normally would not be using this light for vegetative growth, but instead for fruiting and flowering only, so this has been more of an experiment to test California Light Works' claims. This GFP journal is getting off to a disappointing start, to say the least. I can only speculate that since this light is only able to cover an 8 square foot area well in veg, instead of a 16 square foot area, that for flowering and fruiting it will only be able to cover a 2x2 area, instead of a 3x3 as CLW suggests. I'm starting to think about putting an HPS back on these plants, packaging up the light and returning it .

For reference in regards to the dimensions that I am using from the manufacturers website. The 400W SolarStorm I am using is supposed to cover a 6x6 = 36^2 veg area operating at 230w. Having it fail to cover 25% 3x3 = 9ft^2 of that area is a "deal breaker" in my book. If you have any questions about this product SME I would be happy to answer them. Although it operates at 230W it's a 400W LED light that is supposed to be able to grow fruiting plants from seed in a 3x3 area. It achieves this by using 5W LEDs and a very efficient power supply. The operating power with LEDs is lower than the maximum rated power listed on the product. That number is calculated by summing the total power capacity (in watts) of each LED. Having used CFLs, T5s, 250-600W digital HPS lights, my experience is telling me that these lights just aren't there yet.

I know quite a bit about the products since I've been here so long answering questions and helping growers so allow me to make a few corrections.

The light has 80 5w diodes (400 LED watts) but due to inefficiencies it runs at 230w/330w actual draw (depending on which mode is selected) which isn't bad compared to much of their competition. It's not possible to have 80 5w diodes that run at 400w in veg and flower modes. It's assumed that people know that and that's why they (the better manufacturers) put the actual draw watts in the specs.

Coverage claims are overstated (for every manufacturer I've researched) if you want top-shelf results growing cannabis but not everyone grows cannabis. Which isn't to say that you won't get decent results with the areas that they suggest for their lights. Let's do the math:
230w (in veg mode) in a 6x6 = 6.3w/sqft; in a 5x5 = 9.2w/sqft; in a 4x4 = 14.4w/sqft; in a 3x3 = 25.5w/sqft
330w (in flower mode) in a 3x3 = 36.6w/sqft; in a 2x3 = 55w/sqft; in a 2x2 = 82.5w/sqft
(I'll skip the UVB options which add more watts but really don't do much for yield, they're more for quality.)

There is the math; to get top-shelf results you'd want to veg in a 3x3 or smaller and flower in a 2x3 or smaller. If you flowered in a 3x3 you'd still do better than a fluorescent grow but not as good as a 400w HPS but 330w (actual draw) is less than 400w too. The 6x6 area they say "up to" is probably for seedlings.

In conclusion. I'd put LED lights above all fluorescent lights (cfl/t5/etc) and slightly below HID lights. I've seen evidence that suggests that LED lights are very good for vegging if you don't skimp. The flowering results show that LED lights can't keep up with high powered HPS lights but they DO produce decent results and quality. I'd take LED lights over fluorescent lights any day but HID beats LED for flowering for now. Someday LED lights may be as good as HID lights but not today.

There are a couple of theories as to why LED grow lights are under-performing that I won't go into here.

If you were expecting a smaller LED light to perform as well as a larger HID light, you will be disappointed. The question is why did you think that? I think it's due to the LED manufacturers' marketing claims and common LED myths but I can't speak for you. I can't tell you to keep it nor send it back but you should test it before you decide. There are people that are very happy with their LED lights and some...not so much.

Hope that helps...

SME, I apologize for assuming you did not understand how LED wattage is calculated. I've done the math myself, but instead of using watts, I've used photosynthetically active radiation (PAR) measured in umols/m^2/s in estimating the grow area, which is more accurate than using wattage, since this wattage is just a measure of electrical power and not electromagnetic radiation. I used as a reference PAR measured during the summer months of June through August where I live as reported by a public university. I have a master's degree in electrical engineering, a background in computer science and understand beyond your average gardener the lighting technology used and how it should compare if the manufacturer has accurately reported the data they have collected on their product.

I have no intention of growing cannabis with this product, as that is illegal in the United States, but instead am using it to grow my own produce, specifically tomatoes, peppers, and cucumbers. Since this is a "proof is in the pudding" manufacturer sponsored journal, I am putting the manufacturer's claims to the test, which are as we both can agree, largely overstated.

You are right to assume that I am going off of the manufacturer's claims, they have given me a 90 day money back guarantee that they are not misleading me and they even asked me for my qualifications before approving me. They knew that I have experience using 600W lights in a professional greenhouse before sending me their product. The real question becomes why did the manufacturer suggest that the product could compete with a 600W HPS in terms of PAR output measured in umol/m^2/s when it seems more fairly matched with a 250W HPS. I could have purchased the equipment to set up 4 of these lights for the cost of the safety deposit for the GFP... Just because you CAN do something, doesn't mean it's a good idea. Like using T5's or LED's for flowering or fruiting plants, imo.

Also, you haven't made any corrections to my initial post. Everything you said is exactly the same as what I said. 230 operating at veg 400w max capacity on the LEDs themselves 80 at 5Ws a piece. I had a link to the manual w/ PAR ratings, "adjusted" PAR ratings, etc. but for some reason (probably my inexperience with this particular site ) it did not show up on the forum. I also have a map of PAR readings at ground level across the US for Jan-Dec if interested. The light will go back and it will not waste anymore of my time. It will be replaced with one 400W HPS which will outperform it for less than a 1A increase in my power bill. Also, just a humble suggestion, but if you want people to understand that you are a knowledgeable member of this forum, you may want to change your sig. You indeed seem to be something of an expert if you are ready to make corrections to others posts . Your sig made me think you were a complete neophyte.

PAR is a useless marketing measurement, imho. It doesn't even measure the complete specra that cannabis plants use/need. The reason that LED manufacturers like PAR is because LED lights do better using PAR, if they used anything else, like lumens, the numbers wouldn't look good for LED grow lights. I've had this debate a few times here so I'll just point you to another post instead of repeating the same things again:
black-dog-led-t394.html#p5191

PAR may very well be why some people, including you, believe(d) that LED should be doing better than it does but that just proves my point about PAR. There is absolutely no way that a 330w (actual draw) LED grow light will out flower a 600w HPS, despite PAR readings, and I doubt that it would even out perform a 400w HPS when it comes to cannabis. With some other crop like lettuce or algae; maybe...maybe not.

EDIT:
I did correct a few coverage mistakes, etc. and I removed the link because we don't allow linking on the forums (even to CLW) for new members: link-restrictions-due-to-scumbag-spammers-t362.html

Interesting information, once again, I do not and never have grown cannabis. Lumens/Lux usually have been criticized for the same reasons that you are criticizing PAR, i.e. that it is mostly unused by plants for photosynthesis/chlorosynthesis. Most of the data I have seen reported independently of LED manufacturers agrees with my knowledge, but perhaps that is all outdated and referencing the same study? I would really like to see some hard figures and peer-reviewed studies to back up these claims, since Lux is a measure of visible light and PAR is a measure of a chemical reaction. It seems that there is a need if neither is accurate for the development of a new measure. I personally disagree with your belief about a 1000W HPS producing the best results. My technical background and experience has led me to believe that a 600W digital HPS is optimal for gardening, but I have never grown cannabis, so perhaps that specimen is unusual. That is all a discussion for another day, though.

I guess I shouldn't have assumed that you were growing cannabis and coverage/results may change depending on what you're growing. If you're not growing cannabis, what are you growing for your GFP journal?

It's true that most HID manufacturers still use lumens and I guess some people might try to claim that it's because PAR numbers don't look good for HID like lumens don't look good for LED. However, the results back up the case for HID (lumens) rather than LED (PAR) so one is easier to believe, based on results which is what I go by in the real world.

A 600w HPS is more energy efficient, lumens to watts ratio, but since a 600w and a 1000w HPS are nearly the exact same price most commercial cannabis growers use the larger lights to cover more area, increase penetration and save money on equipment. The negligible power savings due to a slightly better efficiency is made up for by a better performing light, yield wise, less equipment needed and fewer bulbs to replace to cover a larger area.