Thanks! I will take a look at the links Brian

Personally I would buy a 3-400 watt LED and not the T5. I have 4 of the T5 units, they are hot, dry out seedlings too fast and aren't good once the plants start getting larger. I have 4 300 watt LED and they are hands down out performing the t5's. With LED's you can grow the plants to maturity, not just seedlings. I am growing peppers, eggplant , cucumbers and Brussel sprouts with the LED's ...

Fluorescent tubes are ideal for cuttings and seedlings.

Led and hid for all else.

Thanks everyone. DBA1954 - can you post a link or give the name/type of the 400 watt LED you are using? Thanks!

my mistake, I have 4 300 watt, not 400 watt I have 3 PlatinumLED p300'S and one King 300 watt. I'm just starting to test the King. I also have a PlatinumLed P150 customized by the vendor to only include veggie bulbs. Works great for seedlings and maintaining plants long term. Probably not as good as the HID (do not really know, never used them) but a lot less current draw then either the T5HO or HID.

https://platinumgrowlights.com/products/p300

and

http://www.amazon.com/KingTM-Spectrum-360-870nm-Greenhouse-Growing/dp/B00V80UQR8/ref=sr_1_1?ie=UTF8&qid=1446915447&sr=8-1&keywords=king+300+watt+led&pebp=1446915449674&perid=1FB55TBB7HA72Y7ZS49E

dba1954 - I'm wondering if there is an update on the King light?

I have 1/2 dozen geraniums under then right now and seem to be doing fine. We won't be planting anything else for a while but the geraniums love it. Depending how much area it's being used for, the king 300 isn't bad. I have it suspended 48" above the counter and it covers 3x4ft suitable for veggies.

Have you started any seedlings with that King light yet? Just wondering if one light 4 ft above the plants is strong enough for sturdy growth of tomatoes and peppers? Is there a reason you have it so high above the counter? Are your plants in front of a window too?

Everyone is wrong. Sorry. Your 8 bulb 4 foot t5ho light will do for instance 6 dwarf citrus until they get bigger then 4. Eventually 2 or 1. Depending on how big you want the trees.

I have 16 citrus under 2 400w t5 ho fixtures. Don't believe the smack talk about them they are no joke. Very even light distribution, very respectable lumen per watt, and if you don't like the spectrum change the bulbs. I even turn off half the bulbs in winter to save power and coordinate their flowering times mimicking winter along with shorter light hours.

people said fluorescent is for seedlings. Bull. What fluorescent? T12 or even t8 are for seedlings. T5 maybe. But t5 ho rival hid for lumens per watt. They are lower but not by a lot.

people recommended led. Do the research. The fixtures mentioned are not drawing the power they claim they use an imaginary equivlenency that is bs. Led put out almost the exact same lumens per watt as a t5ho and less than hid. So a 400w t5 ho will spank a 300w led that really is only 180w like the platinum led linked.

Want a great bang for your buck? Get a cheap magnetic 400w hps setup and when the bulb goes bad or sooner swap it for a Philips master color ceramic metal halide retro white. Insane spectrum beating everything. I picked t5ho due to not wanting the cmh to bleach my carpet. In a basement it's no issue.

Also thermodynamics, 400w is 400w is 400w. Led, t5ho, t12, hps, mh, mv, cmh, it doesn't matter. You will get 400w of heat. Some bulbs dissipate it over a large area like multi bulb led or fluorescent and some over a small area like hps, mh, cmh, and mv.

Mv- mercury vapor (old school obsolete)

hps- high pressure sodium

mh- metal halide

cmh- ceramic metal halide a hps bulb filled with mh gasses. Great design. Flat intense spectrum, everything including uv.

I've had every single type of light mentioned, besides the obsolete mv. Back when I had my medical marihuana card.

400W is not 400W when it comes to lighting. It does matter.

400W from the wall is turned into some percentage of watts of light in the PAR spectrum and some percentage of watts of heat. The ratio can be looked at as the efficiency of the emitter/bulb. HIDs, fluorescents, and especially LEDs vary widely in this respect. HIDs and fluorescents have been optimized a lot over time and have hit their max efficiency for the most part and this level of efficiency has been largely commoditized. Currently available LEDs efficiency varies -widely-, and ranges from worse than fluorescent to better than HID.

1. You did not understand what I was saying. The 400w is 400w is 400w comment was specifically talking about heat output not light. Unused light gets absorbed as heat.

2. I am unaware of any commercial led that tops 150 lumens per watt. 600w hps put out 150 lumens per watt. laboratory led can top 200w but last I knew they were not commercial yet.

Pip313 is irrationally fixated on lumens per watts of electrical input when, as

rooftopbklyn said, the relevant variable is watts of light output within the PAR spectrum per watts of electrical input. These LEDs,

http://shop.stevesleds.com/Philips-Luxeon-ES-ROYAL-BLUE-3-Watt-LEDs-8794102476.htm

have an electrical efficiency within the PAR spectrum of 63% and they are not a laboratory curiosity. According to

http://www.sunmastergrowlamps.com/PAR_Watts.htm

"A 400 watt HPS lamps has less PAR, typically 120 to 128 watts" which implies an electrical efficiency within the PAR spectrum as 100%*128/400 = 32% which is half as much as the blue LED shown above.

You should try a new LED design lamp along side the T5HO's ... I have several of both. The LED units that are labeled "300 watt" (I know you object to this term but so be it) hands down out perform my T5HO 8 lamp 4 ft units (they are for sale if you want to buy them). They draw less power, produce less heat, get superior results and have a 50,000-100,000 hour rating depending on the unit. That's just my experience and it's been a good one. I would stay with the newer 3 watt LED units, I have not tested the 5 or 10 watt but those units are probably more then I need for my flower and veggie growing as they have much higher "watt" ratings. Everyone has an opinion and for some applications the T5's might be good, others the LED. For what I'm using it for the LED's came out on top.

I'm not fixated on lumens, it's just many people use that as a comparison.

link to the manufacturer claiming those numbers for the led. Not some scam website trying to sell them. 63% is too good to be true.

Pip313, did you get burned in the past? I'm having absolutely incredible results (as are some friends) with the LED's ... and we all came from T5HO setups.

I had the 300w platinum led that's recommended. Used it. Couldn't understand why growth was SIGNIFICANTLY less than the 400w t5ho. Then I found out my "300w" led was really 180w. That explained it.

If your led is spanking a t5 ho I have to ask, was your t5 bulbs old? And were they cheap off brand lights?

pip13, did you click azuinsky's link or read any of the page? it states very clearly: "All Tables and Figures referenced are from the LED datasheet. ", and has a link to the datasheet (http://www.lumileds.com/uploads/265/DS68-pdf) by Philips Lumileds, one of the largest manufacturers of LEDs in the world. This particular emitter was released in 2014.

back in October on another thread we had a similar discussion, at that time you hadn't used the P300's... but you trashed all LEDS. please DO NOT lie about what you have experience with. Let the people learn from others and what they can actually do. At that time you actually asked for the Link to the Platinum site !!!!!

The best I could find is 53% typical, at

http://www.farnell.com/datasheets/1484590.pdf

Considering the highest binning rather than middle binning, i.e., "typical," 63% is credible.

Prairiemoon2, One thing to remember about LED lights, there is more usable light. The frequencies are specifically selected for optimal plant growth. This allows for a lower wattage draw and optimized growth.

I did borrow one from a pot growing friend. I told him I needed to try it to see if the hype was real. He got my t5 in exchange for a few weeks.

i used to grow weed legally, I still have about a dozen friends that do. It's not hard to get my hands on any light I want. I setup at least half of their grows with "bubble buckets" some of them I even gave clones to. Also wired some with 220v. Needless to say they owe me a favor or two.

Go to icmag.com if you want to see my past wit some other lights . I have much experience with many peoples grow rooms.

The best I could find is 53% typical, at

http://www.farnell.com/datasheets/1484590.pdf

Considering the highest binning rather than middle binning, i.e., "typical," 63% is credible

Thats is an almost 20% gain. 53 to 63. Very large spread if it can be 20% higher. So can they be 20% lower? Serious question.

pip313 ... you are a pathological liar

Lol. Your a fool

People also told me that about having almost 20 citrus trees in an apartment. Too bad it's true.

Why don't you tell the truth abou how led's wear just like any other bulb and you have to throw away your expensive overpriced fixtures because there is no replacing the diodes?

"So can they be 20% lower?"

I don't know. I own two of those "63%" blue LEDs but I mostly buy cheap unbinned Chinese LEDs. You will have to find out from someone who cares enough to study the binning situation.

I would like people to read this to understand efficacy vs efficiency

http://boards.straightdope.com/sdmb/showthread.php?t=719499

as I said before, you are a pathological liar. You have never owned or tested the p300. people on other forums seem to love the led's and use the t5ho's as heaters. So yeah, it spanks the 400 (actually I think its 432 watts- 54w each) t5ho. you little boy are the fool.

Your funny. Calling someone a pathological liar because your too much of a little girl to even admit it sucks. Keep justifying your over priced low output light. Who the fuck are you to tell me I never used it? It's no better than the ufo I had. Expensive and crap.

be a fucking man and admit that when they wear, and they do, you have to toss it and replace it because it's not serviceable.

i like how you refuse to even address that after being asked to many times.

Platinum led is crap and if it was as good as people claim they wouldn't have to lie and claim a higher wattage than it really is.

look at my 300w light, even though it is 180w. What a load of crap.

that's why you are the idiot little boy. The lights select frequencies. The rating is equivalent my usable light. That's ok. I'm still dumping the t5ho's because the LED's work better. At the end of the day My plants will grow better because of the change. Go back to your 'medical mj' ... lol

do you own stock in their competitors by chance?

Pip313 said, "I would like people to read this to understand efficacy vs efficiency http://boards.straightdope.com/sdmb/showthread.php?t=719499"

Let me refresh everyone's memory. Pip313 previously said, "I'm not fixated on lumens, ...."

The fact that pip313 omitted "luminous" from "luminous efficacy," i.e., lumens/watt, indicates that, despite my warnings, he continues to immorally harp on a variable that is relatively unimportant to plant growth.

Wasted energy going to heat is unimportant? Your numbers refer to the amount of light that is usable.

The name calling isn't productive, I'm not the gardenweb police but please try to polite.

The focus on wattage reported by vendors or even pulled from the wall as a meaningful metric is silly - unless you include a quantitative measure of light from the emitter. (not one "reported" but one measured unless you want to believe lumen figures but not watt figures from a vendor...seems dubious).

Perhaps, for older commoditized tech like flourescent and HID lights are mostly all equal efficiency, and maybe thats where this focus on watts by themselves comes from. But when it comes to LEDs, you can NOT equate watts from the wall with light from the emitter. Perhaps its relevant just to call BS on advertising, but, high watts is not a good thing, its a bad thing. High light is a good thing, at the lowest watts possible.

Most every chinese LED grow light fixture today is sold based on the specification of the emitters it uses. "100 3w LEDs" is "300 watts". Complaining about this is missing the point. It is an accurate description of what you are buying. It does not claim or describe any particular light level, so it is not wise to equate it with one.

Thermal management is very important for LEDs performance and lifetime. The easiest way to make any LED run cooler is to under-drive it current wise, so thats what pretty much every fixture does. LEDs that run hotter than designed for both perform less efficiently (produce less light) and also permanently degrade over time.

The poor quality reputation many chinese led fixtures get is mostly for this reason, Poor thermal management eventually leads to one or more (series connected) emitters to fail, rendering the fixture mostly useless. If you run them for 18 hours a day, 365 days a year, they probably won't last more than a year or two at most. I'm curious if anyone here has direct experience running their fixture that hard.

This says nothing about LED as a technology, but about the quality of the cheap chinese fixtures currently flooding the market. If you want examples of quality fixtures look at places like BML Horticulture. Prices are not in average hobbyist range however. But they also aren't going to fail, and if they do, you will get them replaced easily.

But anyway, 180 Watts from the wall could produce more, the same, or less light than 180 Watts from the wall from a t5, hid, or different LED fixture. And really who cares how many watts. You should care first about meeting your light needs, then worry about doing it for the smallest watts you can. I'm happy to see lower-than-expected numbers from my kill-a-watt.

Also, have you ever used a kill-a-watt on your T5HO fixture? anyone? I have, and my high quality (hydrofarm/envirogro) T5HO fixtures all pull less than advertised. But this matters not at all to me. What matters is if the lights make my plants grow how I want them to. Thats what should matter to you, as well. I'm happier this way than I would be if my lights pulled twice as much power, for sure.

thanks rooftopbklyn . He got me agitated. This was the second go round I've had with him. I'll consider this thread closed.

All I'm saying is you know a scam when they have to lie about what it puts out (300w not 180w) instead of telling the truth.

pip31`3, you don't give friggin up.... are you really that stupid?

Can't come up with a real defence for the fact that the manufacturer has to lie to sell the over priced disposable fixture so you continue with the names.

tell the truth, they lie about its output. You can't service it when the bulbs wear.

Is it your product? Are you the lying manufacturer?