It’s been just over a year since I started using the Mars Hydro 300 watt grow light. Taking a look inside it clearly needed a quick disassembly…
A few LED’s were visibly melted/burned. To be specific, 4 of the blue ones towards the center. I’m not sure if there’s something different about *those* particular 4 (compared to the other blues in this unit), but needless to say, these ones were toast. Before anyone asks, I did check to make sure there had been thermal paste behind them, and there was.
I ended up replacing them with a few cheap white LED’s that I had kicking around, along with some fresh thermal paste.
As to other internals, I found out where the fruitflies had started going once my fly tape was full:
Air compressor took care of things there. I was tempted to replace the thermal paste behind the heatsink (5 screws to detach heatsink from PCB), but the existing thermal paste had it glued on pretty good so I decided to leave things be.
Looking at the fan and drivers…
This had stayed pretty clean and dust wasn’t an issue. I gave it a quick shot with compressed air afterwards since I had it open anyway.
With the new LED’s soldered in, I plugged it in and was up and running….
…except for 1 other white LED that I’d missed.
I pulled it apart later and swapped out that final LED. All was now well!
Thoughts After 1 Year of Ownership
This grow light’s seen various degrees of usage over the last year. Periods of running 24/7, periods of sporadic use on a timer, and periods where it hasn’t been in use at all.
I’m a bit disappointed that 5 LEDs went. It’s generally been well ventilated (ambient temps of 18-24 degrees C), and I really wouldn’t have expected LEDs to start dying. If Mars Hydro cheaped out somewhere, I’d guess it was in the LED brand/quality.
I do really like the rest of the unit itself though. The fan is fairly quiet, I haven’t had a power supply (LED driver) die yet (despite losing a few other drivers in other systems), the thing has a heatsink against the PCB, bypass diodes are used to keep the good LEDs running when an LED dies, and some of the “little things” are there too (bushings to electrically isolate PCB from screws that go into unit, cables nicely zip tied, ample thermal paste used, easy disassembly, etc).