ALERT**GalaxyHydro 300w Full Spectrum LED



You are the new led master electrician and tester… For the peeps in China and now ILGM lol @Screwauger


So the polarity was backwards on the receptacle? Not surprised! The led drivers can be kind of quirky due to how the electronics are configured.

You should be able to get by with minimal to no soldering if that’s something you aren’t interested in doing. Is soldering an issue?

Cost is going to depend on what is actually inside the case, and what you want to do. I’ll try to run through all your options. If you could remove the cover, and get a few pictures of what’s inside I could probably give you more information. Depending on what’s actually inside the light, may eliminate or gain some options. And increase or decrease difficulty. Try to get pics of driver labels especially.

  1. Use factory diodes and replace with slightly larger driver to push them a bit harder. This is probably the easiest light hack. But it could potentially not work as well, due to not having the data sheet for factory diodes. Also probably the least cool in my opinion.

  2. Use factory drivers and replace leds with high power cobs. If the drivers I believe are in there, you would have the option of running anywhere from 3-9. Cost would heavily depend on model and quantity. You wouldn’t be able to increase the amount of watts this way, because the drivers are limited. But you should be able to create a more intense light with less or equal power consumption. Way more cool factor in this than option 1, with probably a pretty good efficiency gain. Cost the same or probably a little more than option 1.

  3. Replace the factory drivers with high efficiency drivers, and the leds with cobs. This will be most expensive, most extensive, and probably give you a really big jump in amount of light. The only limiting factor here will be the cooling capabilities of factory heatsinks and fans. You should be good to about 200 watts without issue. Cost for running 4 of the bigger named cobs would probably start at about $100 or so. Maybe a little more if wanting to get to that 200 watt mark.

  4. Create some sort of hybrid using cobs, discrete, and/or pcb’s. This could be more expensive or cheaper than option 3, depending on which components we use. For instance if you wanted to create a flower only light. We could do 2 or 4 cobs, and then try to find a way to add some deep or far reds. We may be able to this using some or all of the factory equipment, which could lower the cost to being pretty reasonable if that’s what you’re thinking.

You’re really only limited by a few things. Budget, cooling, and practicality. So you tell me what your biggest goal is, and I’ll see about specs and prices.


You da man!!.. That’s cool @Screwauger


Thanks @dbrn32 very much!!

Yes. The polarity was backwards. Old house with quite a bit of previous DIY in the basement. I understand, friend of a friend type deal. I was not in the picture then !!

I am ok with soldering but would need to order the neat little iron I have in my amazon wish list. The 70’s called and they wanted my soldering iron back!!

I will tag you when I get some pics of the dissembled light! Thanks again.



No problem!

I wouldn’t order the soldering iron for this project yet. Depending on which way you decide to go, a lot of them are available with solderless connections.


Hi Screwauger
I bought this same light because of all the good reviews, and so far no problems, but now I’m kind of concerned.

As a long time Amazon reviewer, when something gets a negative review, it’s very common for Chinese sellers to email the reviewer with profuse apologies and seemingly generous offers, such as a replacement without needing the old item in return. They aren’t allowed to ask you to change your review, but that’s the deal and many people oblige, even though good customer service is supposed to be in a separate review. It’s another form of review manipulation, and allows shoddy products to continue to sell with 4 and 5 star reviews. Reviewers also aren’t allowed to accept free merchandise in exchange for a review.

Sellers also like pics and videos because they tend to get better placement on the review page. The thing is, when a seller is suspected of manipulation, in order to keep selling they will be asked to turn over the names of reviewers who accepted free products or changed their review. The reviewers can be banned while the seller just gets a little slap.

Just something to keep in mind. Thanks for posting.


Hi @Grandma

Couple of things:

Thanks for reading my thread and thanks for your comment.
I am not really sure what you are “concerned” about.
Point of reference, I contacted the seller, and I demanded restitution or compensation.
The seller did not ask me to change my review nor did they ask me for a favorable review.
It seems you are implying the LED is shoddy and that perhaps, I’ve been manipulated into giving a favorable review despite the mechanical issue with my light?? But I suck at riddles so apologies of I am reading that wrong.

I am going to give you the benefit of the doubt and assume you did not read my entire thread. My light was not faulty nor do I consider it shoddy, it turned out the fault was in the house wiring vs the light.

Excuse me if I have misinterpreted some or all of your “concern” but if by chance your concern had to do with the HG 300w LED you purchased, I can tell you you purchased a decent LED that is used by several on this site who grow excellent crops. Take a deep breath and grow on.


I think she was more concerned that the light wasn’t as good as she originally thought it may be. And that perhaps there are several other instances like yours, and that if they weren’t giving away replacement lights the reviews would be much lower.

That’s the way I read it anyway.


@Screwauger that freaking awesome bro
Woohoo 4 lights so cool they stand behind there products my friend


Hey @dbrn32

Would you mind taking a look at the guys cobs at a site called cobshop. He builds them specifically for autoflower plants (not sure what makes them that specific) and I am interested in knowing you frank assessment.
Thanks and I believe it’s the first choice on a google search and has a net extension.


@Screwauger he seems legit.

Those are buildable as well if you were thinking a single cob application would be better for you. He doesn’t give driver info, but I’d say those are running somewhere in the neighborhood of 50-60watts.

For comparison, you could source the parts to build a 200 watt cob light using 4 citizen cobs for somewhere in the $200-$250 range I think. Hlg-185 is about $50’ and about $20 per cob and $20 per heatsink. Allow yourself $20-$50 for other misc building materials and you’d be there, compared to over $500 for buying 4 of them.


have two 300’s no issues yet - happy with lights -


The fact that the LEDs went out when you unplugged it was the dead giveaway that it was a wiring problem. Timers generally only interrupt the hot wire. If the plug is wired backwards, the timer interrupts the neutral wire, and you still have some power going into your light driver. The driver would see this as voltage between neutral and ground, and this driver design leaked a little current out to the LEDs.

Funny thing is that if you used a two prong plug to go into your timer (no ground) it would not have happened. But don’t rush out to buy two prong equipment, everybody. Three prong wired correctly with a GFI is much safer. Two prong might have a connection between what it thinks is neutral and the driver box, which would give you a shock if you touched it and a good ground.


So far, my 2 300w & 1 600w are doing a fine job. Second grow using same lights.


Hey there Screwauger, I am having the same issue with my Galaxy 300 watt light. I unplugged it and 10 or so diodes were on and some were blinking. Freaked me out. I have also had some problems with leaf burn on the upper leaves. The light doesnt seem to spread out very well either. I had 1 over my 4 flowering plants and they werent getting enough light and they were not using the nutrients very well. I cut the nutrient formula in half and they recovered but i still have to keep rotating them under the light. Just tonight i decided I’d had enough trouble with them and I just ordered a t5 fixture to replace them. ( I have limited height available and cant use a 250 sodium). I thought I would try the led technology and I will say I don’t like it. I used to have a much bigger setup. A 400 watt Halide and a !000 watt sodium and I never had any problems with that. But now I dont have the room for that. ( I moved to a different state and a new house and a lot of the friends that I had are not close by anymore so I dont need that quantity.) I’m using t5 on my veg. and as soon as my new t5 and red bulbs get here I’ll be using that for the flowers too. What do you think of t5?


How far away from the canopy are you hanging the light? I was about 18 - 20 inches. Burned them


Never used a t5 but I know several who do and they seem to work well.
Where did you get the led that is not working right?
I started out at 18-20 inches but I gotta say I had 3 and 4 lights in my tent and I found I had to keep them much higher than that, like as high as my tent would permit like 34" at first and until the plants were more mature late veg/flower then I lowered to 18 or so.


My 300w seems perfect at 20"-24", and the 600w starts at 36" & gets slowly lowered, until the plants tell me enough is enough.


I got mine from Amazon too. And as I read down through the posts I realized that my house is older and was not wired up with proper ground. Don’t know about the polarity. I have a short space for growing and I wish I would have known about the height requirements for these type lights before I bought them. I think they are good lights, just won’t work for me. Thanks for the reply. Do you have any recommendations for a short strain of weed? Growing green crack right now. (Hate the name) and it’s working good. But… Variety is the spice of life right😁


Use photo plants with a light heavy in blue wavelengths for vegging, top them and they should be relatively short as long as you have enough light intensity. Then just change light schedule to 12/12 when they are 1/3 to 1/2 of your ideal maximum height.