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Thread: Small (ahem, cheap) LED COB lights on Amazon. Good idea or false economy?

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    Default Small (ahem, cheap) LED COB lights on Amazon. Good idea or false economy?

    As a budget grower I'm always looking for little things to add to my grow room to improve stuff, especially if it's a nice price. Obviously, cheap is actually often rubbish and complete waste of money, but it's always interesting to look and evaluate what is out there. I remain healthily sceptical, but budget LED lights - while initially scorned and mocked, have found their niche with hard up growers like myself - lots of new growers are appearing on this forum and having a bit of success with their Mars LED's and a host of similar brands at lower prices. Yes, I do believe you still get ultimately what you pay for, but if the most you've got is around £80-100 then have become a viable option.

    So, with that backdrop, I've been looking on Ebay and Amazon and noticed that lots of cheap COB LED lights are for sale. Now, I've actually got a CRX Sunny COB unit that is pretty good, but attention has been drawn to low cost, single COB units. Here is an example I've found on Amazon UK - search ref: B078H9SW95

    It's advertised as 50W - which is probably crap - as we're all familiar with cheap LED's having their true power somewhat exaggerated - sadly I can't find a value that indicates it's true power, but I'm wondering if these have some benefit as a supplementary light? I remember when I switched to LED from a CFL light that I was often encouraged to utilise the CFL as a supplementary light - to get extra lighty goodness on the plant, especially in terms of lighting the lower canopies of my plants in the latter stages of a grow. This turned out to be impractical - mostly for space reasons, however - these lights are small, have built in stands so they're designed almost perfectly for that purpose - i.e. getting light onto the lower reaches of a plant. I appreciate they won't be powerful - but at close range, will they compliment the bigger lights from above and get good extra light to the lower buds that might ordinarily end up as pretty useless popcorn bud? At £20 I'm slightly tempted. What do you guys think?

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    I'm really inexperienced and have been wondering the exact same thing. I've got a cfl set up just now but have a small cheap led grow light somewhere in the garage from when I thought about growing a few years ago then paranoia got the best of me and I bottled it.

    I think in principal it sounds solid idea but I really don't know much!

    How do you find the difference from cfl to the Mars led, they and a few others seem quite popular just now.

    Cheers

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    Quote Originally Posted by Hashhound View Post
    I'm really inexperienced and have been wondering the exact same thing. I've got a cfl set up just now but have a small cheap led grow light somewhere in the garage from when I thought about growing a few years ago then paranoia got the best of me and I bottled it.

    I think in principal it sounds solid idea but I really don't know much!

    How do you find the difference from cfl to the Mars led, they and a few others seem quite popular just now.

    Cheers
    If I'm being honest - I didn't do enough CFL grows to be able to get a great comparison. I think I did all of my first grow with a 300W CFL Dual spectrum bulb, then got a Mars300 on sale from Amazon and switched over right away. I've been tempted to start off a grow with CFL as that first grow had almost no issues in the early part and my grow environment was absolutely at it's most basic. Waiting to see how my latest grow goes - had a couple shockers last year experimenting with a newer, bigger LED. Since about my third grow I've always felt the next one will be a big haul, but it hasn't quite turned out that way!

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    Sometime there will be jewels within the budget range so it's just a case of doing as much home work as you can.

    Enough wall watts
    Any PAR info
    Spectrum info

    That item number youve selected I would say is dubious with this in the description

    5. Full spectrum COB light source, wavelength: 620-630nm

    But then again probably just a warehousing stockist that doesn't really know what he's selling

    At 20 quid at the least it going to be ok for seedlings

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    Quote Originally Posted by mysticjim View Post
    If I'm being honest - I didn't do enough CFL grows to be able to get a great comparison. I think I did all of my first grow with a 300W CFL Dual spectrum bulb, then got a Mars300 on sale from Amazon and switched over right away. I've been tempted to start off a grow with CFL as that first grow had almost no issues in the early part and my grow environment was absolutely at it's most basic. Waiting to see how my latest grow goes - had a couple shockers last year experimenting with a newer, bigger LED. Since about my third grow I've always felt the next one will be a big haul, but it hasn't quite turned out that way!
    Good luck man with the grow. From what I've seen led growing is still being perfected

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    Quote Originally Posted by gardro View Post
    Sometime there will be jewels within the budget range so it's just a case of doing as much home work as you can.

    Enough wall watts
    Any PAR info
    Spectrum info

    That item number youve selected I would say is dubious with this in the description

    5. Full spectrum COB light source, wavelength: 620-630nm

    But then again probably just a warehousing stockist that doesn't really know what he's selling

    At 20 quid at the least it going to be ok for seedlings
    Yes, that bit did worry me as bigger, dedicated grow lights seem to mention a wider spectrum. I think LED light bulbs look a slightly better option. They'll fit in a standard E27 fitting and the wattage is pretty much genuine.

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    Quote Originally Posted by Hashhound View Post
    Good luck man with the grow. From what I've seen led growing is still being perfected
    Well, yes and no. About 5 years back there was almost universal scepticism, mostly from HID/HPS growers. There is no argument that a basic HID/HPS setup will deliver better results than a cheap LED (but this does depend on the growers enviroment generally), but cheap LED's have certainly nudged in alongside CFL as an entry level option in terms of low heat/high stealth/bang for your buck type stakes. They have found their market and the tech is still being refined at the top end of the market, so those improvements will filter down gradually. LED is certainly an incredible technology for light in general, so they're here to stay, but yes, the growing techniques are still being refined and the potential drawbacks discovered.

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    a HID/CMH is definitely what you want for a good heavy crop of potent weed,
    for veg a T5 is hard to beat for light spread and watts/heat used,

    For a real good flowering LED with decent watts you are easily talking £600++
    for most it's just too much to invest when you can buy a good 600w ballast/bulb/shade for £160

    i do agree leds will become the lights we all use at a much later date,
    Currently they just aren't there, but with every passing version they get better but also more expensive,

    same as Widescreen tv's at the very start, they were expensive but now rather cheap,

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    Cheap COBs from ebay... no, not worth it.

    I bought a selection of 20w and 30w chinese chips off ebay, and some Cree cxb (this was a few years ago when they had just brought out the cxbs, 30% more lumens/watt!). I set equal systems up (one chip mounted on a cheap CPU heatsink & fan (<£5!) I run the 12V fans with 5V from a USB charger, they turn enough to stay totally cool but are completely silent. With the fans off, the heatsinks get to about 35-40 degrees.

    Verdict: The Cree chips gave out over double the lux at 8" as measured with a light meter for a 30W setup.

    Also The LED driver from the chinese companies also got pretty damn hot. The branded driver I got with the Crees (about £15 each) stayed mildly warm at most. Multimeter says the chinese circuit was drawing over 40 watts compared to ~32watts for the cree. The cree cost about £20 for a 30W module - cob, driver, and proper mounting (no need to directly solder anything, just tin the wires, press them into the mounting, and screw it down over the cob). Easily 4x the price but lux/watt is at least 3x what the cheap chinese chips do. You really get what you pay for.

    Also, anything over 20W from cheap chinese places is also risking quality issues. I saw a youtube of a guy who tests these, and the chinese chips work with 1W LEDs in strings of 10. But, any flaws mean you can get a 30W chip with 3 strings of leds under the phosphor, and only 2 of them work. You won't be able to tell by eye unless you have a welding mask, or an adjustable voltage supply like a lab bench supply. The 10W ones were fine, cos when they go, the whole thing is dark, but you would be hard pushed to tell is a 30W chip is only giving 20W just by looking at it.

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