Led Vs. Hps - 70w Challenge

[LED_experiments]

ok, so i guess i missunderstood your previous post, my bad. i agree this comparison will prove that hps will win this time. the cause for that is not the setup. we won't get the real results this time.
i'm sure when you started using hps for the first time, you didn't get as good results as you get now, after years of using hps. you had to learn how to use it to get the best results. it is the same story here.

yeah i wish i could do more research. just not enough hours in the day. but i also believe it is as it should. not everyone should research every single topic. it wouldn't be productive. we need to rely on each other doing different kinds of research and summarizing our findings.

so how about a summary for us in this case? what factors do you believe contributed to this problem?

i know the feeling when there are at least 10 hours/day missing. so you are right, there is no way everyone can know everything. i also don't know much about using hps (believe me or not, i haven't grown a single plant under hps) and many other things. if i need to know something, i ask the person who i know that knows as much as possible. there on the other hand always are people who want to look smart and start giving you suggestions even they don't have any idea what they are talking about. you just have to decide who you will listen to. no hard feelings, i didn't mention any names.

making a summary would be a bit hard because i also still don't know everything about ledgrow (even if i started with researching that technology more than 2.5 years ago). so i won't give you the exact informations, just my oppinion what should be done to get better results:
-screen should be lower so that the lower branches reach the net sooner, screen should have smaller holes so thatyou can handle the plants better and the light can be placed closer
-veg time should be longer (most of you guys convinced medved to switch both places to 12/12 at the same time). the point is to get more budshots/branch lenght, so if using more time, there would be more of them and the net would be filled to the proper percentage - in this case we should measure g/kWh not g/w at the end
-co2
-hydro
-different spectrum combination (as i said, we are still testing different lamp configurations)

what reasons do i have in my mind for causing the problem:
-ventilation in this drobe should be changed. led plants get the air that hps plants used before (they use co2 and the led box gets less co2 even if the plants need more of it than hps plants)
-temperatures
-fertilizing (it would be much better to run hydro where you could measure nutrient uptake)
-overwatering
-some kind of lockdown or lack of some elements because of unknown reason (i remember david zap always having Mg problems in his led grows)
-problems with setup (i doubt about that, but there is an option)
-ph problems
-bad karma
...

there are many things that could be wrong. i just listed a few of them but because i don't know much about plant problems and i'm not sure what it looks like if it has a certain problem, i most probably missed a lot of possible reasons.

 

[Guest]

i completely agree LED_experiments, this is a new tech so it needs to get its feet wet still

 

[Medved]

I think that PH must be the problem in here and because of the PH there was some nutes lockdown. I grow indoor for 4 - 5 years, and nothing that strange haven't happened to me before. Only at my first grow a few females was killed because of the sugar inside the water (love to experiment). It's very wierd that only DCSkunk girls are so fuckin wierd. Ak-47 is still looking normal. I flush all DCSkunk girls with 10l of water with 6.5 PH. And hopping for getting better. I take them from the closet(because of the flushing), so I remove the net. The girls are still smelling nicely. The next experiment I hope that I will be home for whole experiment, so nobody else will visit my plants Sometimes the smallest details are the major problem :S I hope that tomorrow will have some time to take some more pics, maybe a movie, but I don't like to make movies, that there are no nice things on it

And I have to admit, that I was thinking about hydro, but that will be first time for me, so I think that I will stay only at thinking

Have a nice day and fingercross for my DCSkunk

 

[budvapor]

no hard feelings, i didn't mention any names.

sure thing. thanks for elaborating on your assessment. few of us have the luxury of being able to test all those combinations properly due to govt corruption. this is why a forum like this is so vital! we all test things, improperly, but as a group we can share and make progress.

i hear you about experience too. even though i'm myself extremely inexperienced, i've already learned how there's stuff you can only learn by experience. or maybe it's just me hehe, i have to learn the hard way

I think that PH must be the problem in here and because of the PH there was some nutes lockdown.

i hope the flush works for you here. still i'm curious why you think it's PH. i was looking at a book here (grow great marijuana by logan edwards) and it says ideal ph range is 5.5-6.2. so even at 5.5 you shouldn't have any nute lockdown problem...? i've freely admitted i have little experience, and i'm always wanting to learn more, so am i misunderstanding something about PH here? did you check the run-off after the flush?

re-reading a bit i saw some posts about temps reaching 35 C... that's pushing it according to what i've read, unless you have some heat-resistant genetics, but even then, in the small pots you have, i'd be concerned about temps for the roots...

great effort either way. we're all learning something here i think!

 

[LED_experiments]

i hate being constantly out of money and living in situation like i do. if i was a member of a rich family and living in country where laws about marijuana are not so absurd as in my country, i'm sure i would have a growhouse (not growbox or growroom) with a lot of drobes, tons of leds, many different spectrum combinations and i'm sure i would find the configuration we are looking for in maximum 2 periods of grow. if i win a lotery, i'll move to some other country with better laws and make my dream come true.
but the reality is far away from that. i don't have the money, i don't grow because of the problems i'm having with the law and therefore i'm looking for guys like medved who are willing to spend some money in my experiments and test my setups. too bad there is not many people that are willing to test that stuff because (as they normally say) nobody ever seen good results of ledgrow. they decide to buy a lot cheaper hps and grow with that. i totally understand them. it is cheaper, you get more buds, the electricity is not that expensive and there is no problem for them to use a AC or a good ventilation.

 

[Boerman]

then essentially this experiment has proven already that hps does muuuuch better...the led plants can even handle the feeding regimen any longer

It doesn't prove that at all. Not trying to be critical, but from the beginning I felt that the test grow design was flawed. When you are doing a comparison grow, you want as few variables as possible. Stacking the two grows creates an extra variable - temperature. Even a 70w HPS generates a significant amount of heat. Having the LED plants above the HPS chamber means that the LED roots, and for that matter, the whole plants, are going to be hotter. They will, therefore, need more water because they are going to transpire more and there will be more evaporation from the grow medium. If you water them more to compensate for their increased need, then you have just fed them more nutrients, which may lead to nute burn. It could also lead to better performance for the LED if the extra nutes are not too much.

All this still may not be what is the problem here. But because the design creates differences between the two grows that may effect the plant growth, health and development, you can't come to the conclusion that the current problems mean that either light, itself, is better or worse.

 

[Boerman]

So much good information here!

LED experiments, you have inspired a lot of good thinking. As much thought as I put into my side-by-side test grow, you just showed me something I missed. I considered temperature in terms of ambient temps for the plants and temps for the root zone. But I didn't consider it in terms of uptake of nutrients. That is why I was so surprized this morning (day 12 of veg) to wake up to obvious Ca/Mg def on the LED side. I thought "how can this be?". The two plants are clones of the same mother, taken and rooted at the same time, under the exact same conditions. They are in the same flood/drain table, getting the same nutes at the same time. They are just divided by a partition that keeps them under their own lights. But now that I think about it, it makes sense that the radiant energy coming off the 400w MH light is going to cause more transpiration and, thus, more nute solution uptake. Conversely, the cooler LED side is going to transpire less and will take up fewer nutes if the solution is the same strength, which in this case, it is exactly the same. LEDs aren't just going to change our power consumption and heat issues. I think we are going to have to completely re-evaluate our nutrient regimes, as well.

I wonder if any of the nutrient companies are on the ball enough to be doing research on this aspect of indoor growing. If LEDs are the next big thing, and I think they are, then we are going to need different nutrient formulations. Whichever company gets out in front of the pack on that will stand to make a bundle.

I hope people reading this thread and others on this subject will come to see that there is no way to do a "fair" comparison between growing with HIDs and LEDs. At least not when you are looking at the input side. That is because they are two different things. It is like comparing cars to airplanes. You put some fuel in, turn it on, and go. The start and finish may be the same, but how you got there is quite different. The best test to me with these lights is when you grow each light method the best you can for that method. Forget what the other one is doing (how high the light is from the plant, how strong the nutes, etc.) Just do it the best you can for that method. Then when you're done, how much did you spend for what you got? Kwh/g to me is the main question to be answered. Because what we are really looking for is efficiency. Get the most for the least.

 

[Boerman]

By the way, I really should have thought of the uptake thing. I run aero. In the cold months, my temps run 50-70. Summertime it's more like 70-90. If I don't run with lower ppm's when it's hot, I get nute burn. The plants just can't use all the stuff that is coming mixed in with the water they are sucking up to "sweat" out.

 

[Medved]

just back from the girls

2 DCSkunk I think they are getting better, 1 DCSkunk looks very poor

Have a nice sunny day everybody

 

[pumpkin2006]

Dunno if you looked yet... but LED's do grow plants and well: http://www.icmag.com/ic/showthread.php?t=63943

He used recycled organics (would be good for LED experiments).

 

[LED_experiments]

pumpkin, thanks for that link. i heared about that guy and tried to get his thread at that other forum but they shut it down before i got there. the bad thing is that he don't share any info about the lamp. ok, it is his choice. if he decided to be a businessman and make business with that, no problem. i decided to share all informations about my setup in order that anyone that finds my lamp good gor growing in his drobe can build one.
i noticed he got over 160g from that 125W lamp. well, this lamp that medved uses runs at lower wattage (just arround the half of watts that he uses) so in this case if the yield is 80-90W the results are the same (g/w ratio). but in this grow i doubt medved will get that because of all the problems he had and because he still needs to find out how to use it for the best results.

as boerman said:
'The best test to me with these lights is when you grow each light method the best you can for that method. Forget what the other one is doing (how high the light is from the plant, how strong the nutes, etc.) Just do it the best you can for that method. Then when you're done, how much did you spend for what you got? Kwh/g to me is the main question to be answered. Because what we are really looking for is efficiency. Get the most for the least.'

btw, there are many things that can be compared according to what is important to grower. for example:
~you have a 0.5×0.5×2m drobe that you can use for growing (let's say you have space limits). if you take 250-400W hps and put it into that drobe, you have a 0.25m2 growspace (1 level). if you choose leds, you can make 4-5 levels and the grow surfance in the same drobe is 4-5 times bigger than if using hps.
~you have $2k to spend and you can buy some hps lamps or a quite good led setup. you can compare g/w, g/kWh you got from lamps, g/$ you spent for the setup, grow space/$ you get in each case, g/life time of the setup, harvest/year in each case,...
there are many things, not just g/kWh. in every way one of the lamp types has it's own advantages. it only matters what is the most important to you and what advantage you are looking for. from what i hear/read the biggest dissadvantage of the led setups is their price. but that is going down quite fast and the technology gets better. i remember when i started my experiments. i spend much more for the material and the lamp only had 50% of the output if comparing it to medveds lamp. next year maybe i'll be able to find the material for 50% of the price that i payed for his material and the leds will have 200% of his lamp's output. as you said, just like computer technology. you buy a PC for $1k, after a year you can sell it for $200 maybe and the PC you can buy at that time for $1k is twice or three times better than the one you bought 1 year ago.

medved: glad to hear about your 2 dcs getting better. too bad the third one looks poor. maybe there are some strains that are better for ledgrow than others. i remember AK having problems in veg time for unknown reason, now dcs having problems while AK is doing ok,...

 

[3dDream]

So how would you keep the next test fair?

- 2 Separate cabinets?
- No nutes? Just plain water and soil. I know the yield will suck, but nobody knows if a plant uses nutes differently with LED.
- A wick/autopot.. something that uses a reservoir. this way the plants drink what they need. HPS should drink more than LED due to heat. You could be over/underwatering. This method will eliminate that variable.
- Glass between the lights and plants to remove heat.

Yes No?

 

[highonthechroni]

High Medved

Interesting thread, good luck with the sick plants.

 

[Medved]

The girls are in 41 days of flowering. And the HPS box is looking much much better. What do you suggest for test grow #2? any changes? i'm really angry on my fuckin vacations, maybe if I were at home, than I will not have those problems, just maybe, can't blaime everything my friend for.

HPS room


one DCSkunk looking better


one DCSkunk looks like dieing


one small bud from AK-47


3 AK-47 under leds


one LED bud of AK-47


Have a nice day everybody

 

[Boerman]

So how would you keep the next test fair?

- 2 Separate cabinets?
- No nutes? Just plain water and soil. I know the yield will suck, but nobody knows if a plant uses nutes differently with LED.
- A wick/autopot.. something that uses a reservoir. this way the plants drink what they need. HPS should drink more than LED due to heat. You could be over/underwatering. This method will eliminate that variable.
- Glass between the lights and plants to remove heat.

Yes No?

First you have to understand that the smaller your test sample/the less reliable your results. Ideally, your test would include thousands of samples on each side. Many of us have had the experience of growing two clones side by side under the same conditions and still having noticably different results. Most likely, none of us here can test a large sample. But at least you can do your best to assure that both sides of the test are as close as possible to each other in terms of growing conditions. When you notice a difference in results, ask yourself what could explain the difference.

For myself, I built a cabinate 5'x3' in a small bedroom that I am not using. Inside that I constructed a flood and drain table and put a divider in the middle to separate the lights. Three sides have walls - one side is open. This allows for temps to pretty much equalize. It can't account for radiant heat from the HID bulb. I then selected two clones that had been taken from the same mom on the same day and were identical in size. From there I have been growing both sides as individuals. By that I mean that I am trying to get the best possible results by adjusting the light height from each plant according to what I think is appropriate. Distance from the plant can be somewhat "in the eye of the beholder". I don't like to risk burning the tops, so I am keeping the HID about 18-20" from the top. But I also am not just sitting the LED right down on the top either. Temperature-wise, I could do that. But I chose not to because when you are growing more than one plant, you will have to have the light higher to have wider coverage. Also, I am not trimming/pruning the plants. I think to do so might prejudice one side or the other.

I tried to do everything I could to make the test "fair". But "fair" can be somewhat illusive. Are we really looking for "fair"? I am not really looking for fair. I am looking for "best". Both are terms that you need to define for yourself. For me, fair is giving both sides your best effort, not necessarily the same treatment. Since the two kinds of lights are so different, you can't really treat them the same. Is that fair? I think it is if you do your best on both sides.

After only two weeks, I can already see one problem with this test design. After about a week of veg, I noticed a nute deficiency on the LED side. This is where you ask yourself what could cause the difference. In my effort to assure that both plants got the same treatment as far as nutes are concerned, I didn't take into account that the radiant heat from the HID bulb would cause more transpiration from that plant. If you stick your hand in there, it doesn't feel like a lot of heat. But you can feel it. When the plant transpires, it pulls up nutrient solution to replace water lost in transpiration. If it pulls up more solution, it pulls up more nutrients. Conversely, when the LED side pulls up less solution, it gets less nutrients. In this case, the LED side is also growing taller and faster than the HID side, so it needs more building blocks than the HID side. Hence, nute def. If I do another test, I will make it two separate flood and drain tables with slightly stronger nute solution on the LED side.

My personal conclusion is that there will always be some aspect of a test that someone can point to as a "flaw". If you are going to set up a test, give it a lot of thought. Look at tests that others have done and see what you like or don't like about them. Read what others have commented about those tests. Then design your own test in such a way as to address the shortcomings of those who have gone before you. Always look for ways to improve.

 

[GratefulDude]

man o man.

 

[lc00p4]

wow, a lot has happened since i last checked in! your plant will bounce back if you give it the tlc it needs. how many days left for each before you get to the weigh in?

 

[Medved]

lc00p4 what is tlc?

yesterday I choped first one, the sickest one. Now there are only 5 girls in the LED box.

And don't know how many days to the weigh in, I think that DCSkunk will finish much before AK-47.

have a nice day

 

[yeshwa]

Hey Medved, do you have all the wavelengths covered for both chlorophyll a and b?

The Peaks are:


I understand that you can't get LEDs that are specifically those wavelengths, but you can get ones that are near them. The LEDs that you are using, did you buy the wavelengths that are specified only for one type or have you covered all the peak wavelengths?
Say you only bought 660 NM LEDs and 430 NM LEDs, you'll only have chlorophyll a covered while chlorophyll b is not absorbing any of those wavelengths.

Sorry, if you already have this covered. But if not, I think that would dramatically affect how your plants will turn out.

 

[LED_experiments]

if you would read the thread, you would find all the answers. there are 4 different types, not optimal but close 410, 465, 630, 660