Lighting Is there such a thing as too much LED light?

[Groff]

Hi guys,

Going to buy a LED light pretty soon. I'm going to buy direct from China, so cutting distribution costs, so for the same budget I can get a higher output light.

I know that with some strains + LED too close to canopy, you can have some bleaching effect (recuperable with foliar cal mag). With HID's, the problem is heat excess.

So is it worth it to get for example a 500w 7 band 3W for a 4 plant tent, or would I be ok with a 300/350w (and cut in bills too).

I've only ever used a 600w HID before, which is a bit of an overshot for my tent solely because of heat. I managed ok, but with some headaches...

I want to grow maximum bud in the minimum space (don't we all...?) - but I went overboard with the choice of 600w HID and don't want to make that mistake again.

4 or 5 plants max at any given time... 1,65 x 0,65 x 1,8m tent size...

 

[agito]

air cooled hood and reuse the 600w hps IMO if using 1 source
your tent is a funny shape you would imo if using leds require 2x lower wattage pannels like blackstars to get the most from it
or a shed load of t5's

 

[Groff]

I really want to ditch the HID. too much on the electrical bill aswell...

Yeah, I have thought of that too... but in terms of total LED wattage, what would be the cut-off for "too much" ?

From what I've seen around, 350w seems to be ideal, but as always trying to get the best bang for buck deal

 

[astronomy420a]

get the largest led you can afford! for the future? because you never know what you will try to grow next! it might be more than you need this grow, but not the next. i have three plants in my tent and running all the time and run 375 watts of led and 450watts of cfl equivlent. and i would like more!!
you can put any size led in a tent you want, if it's a huge led, run it a little further away!

 

[agito]

Well 2x 240w is a better idea but china brand are normally crap
That pannel is 4ft across it wont light that area right dont fall in love with the number light spread in a .65m width tent is the issue ive never seen 1 panel light 1.65m i dont think 1000w hps will do that

you asked for max bud but dont want to pay the leccy bills for hid Mmmm

options are
keep tent
buy 2x led panels (good ones)
or buy a bank of t5's like
or buy a 1x1m or 1.2x1.2m tent with a cool hood with 9 plants and rape a shed load of bud

max cut off wattage in a 1sqm probs going to be 500w-600w for quality leds if evenly spaced out which yours is not but you can just lift it a touch higher

 

[Groff]

Yeah, its an odd shaped tent (Hydrolab) but I chose it because it fits my indoor stealth perfect!

Agito, good points there. That is why I am looking more into PAR values than light spread. 3w chips, covering both veg and flower. I checked, and it could be cheaper even to buy
2x 240w blackstar type panels, than a 1x 350w.... but the problem if finding the combination of right spectrum + led chip + shipping cost (the vary from free to expensive)

 

[agito]

2x240w black star would be awesome in there with the 3w chips
just had a thought silly me the 2x180w black stars with the 3w leds would be awesome as well if that helps

ask muddy on spectrum id think the blue is more available to plants in general

 

[Bonzo Mendoza]

I am in the process of switching from HIDs to t5ho.

At least in 2012, I do not agree with LEDs for growing because (compared to t5ho) they are way too expensive. Both LEDs and t5ho are equally capable of 70-100 lumens per watt but LEDs cost 3x the price (per watt) of t5ho. They are equally efficient, especially now that Spectralux t5ho lamps are so easily available.

But in three years, when LEDs are available for $2 per thousand lumens of LED .... then lets' take 'nuther look. (right now, roughly: t5hos = $5 per thousand lumens; HID = $4 per thousand lumens; LEDs = $12 per thousand l)

I agree that HID's are a pain in the ass - t5ho bulbs last for 20 gro seasons while HID (hps and mh) only really last for 1 or 2 gro seasons. Also, HIDs' are difficult to hide. The one thing I really like about them is that there is a 15 foot cord between the ballasts and the lamps - this makes it easy to either isolated the hot ballasts from the grow room (when I don't want all that heat) or (in Dec and Jan) place the ballasts in the gro room to keep it nice and toasty warm.

Compared to LEDs or t5ho, a thousand watts of HID (enough for 18 three gallon containers in my set up) is in fact fairly costly by the way - here (in Neo-Facist Amerikkka) for a 20/4 schedule, 1000w costs about $1.50 per day - a 1000w HID on 12/12 schedule costs 80 cents per day. If I used t5ho's instead, (for a 20/4) then I could grow 16 3 gal pots under t5ho's for $1/day.

But to answer your question: YES, there is such thing as too much light. Unless you are using a co2 system, what's the point in more than 6000 lumens per sq. foot??

Do not underestimate the heat produced by LEDs (and you cannot isolate a hot ballast outside your gro tent with an LED; same problem with t5s). But especially with cheap Chinese LEDs, lighting efficiency goes way down (and heat generations goes way up) as the LED gets old.

 

[Groff]

Hey Bonzo,

Thanks for the input! Even still I think I prefer LED. You can configure spectra, you can replace parts easily (if you find the proper company, but the good ones are great!), lifespan is lots longer, plus failure with a t5 is hazardous, with LED its perfectly manageable. Plus, electrical bill is still a deal breaker. Within a year it is payed for easy! And future upgrades is possible for a fraction of the cost, say replace an array with a specific diode, angle, etc.

It makes sense to buy 2 panels instead of 1. Regarding spectrum, would you go for 2x vsg & bloom, or 1 veg + 1 bloom? I wish there were more threads on spectrum for growing. I have come to my own conclusions, but still a bit shaky...

 

[agito]

IMO you would want the plant to get as much food as possible which seems to point to blue absorbed better than red i would get a panel with a higher blue to red ratio but would still contain both spectrum's plants till use other spectrums i did post an article on here that nasa found using a couple of green leds increase growth vs no green at all

To be fair long as you have both spectrums in there i would not worry about the ratio to much but a few whites may help fill in the gaps

Dont want to be a downer but experts would still say led currently is overrated but not to say you wont get good results