I bought a 48" jbj Formosa DX - JG3 fixture online a few months ago. It was fine for a few weeks and then all of a sudden there would be this horrible noise when the fans came on via analog timer ( the kind jbj says to use with fixture), which sounded like a 747 taking off. The noise would go away in a couple of minutes, so I let it go since according to what I have read, the noise wasn't "abnormal" for jbj fixtures. Shortly afterwards, however, I noticed that the middle fan of the 3 fan system wasn't even running.
I contacted JBJ and they sent me some new fans - the same type that were already in the fixture. I had the same problem with them so I made it a point to find out exactly where the noise was coming from.
As it turns out, the power cord to the right front bulb ( as you're looking at the front of the fixture) has the thick power cord insulation around it and that was rubbing against the center fan. I tried to remove the outer insulation, to push it over, and everything I could think of to get it more out of the way ( creative zip-tying included), but no matter what it would move back over and rub into the middle fan. The fan on the back would catch the fan power cords, so you could hear the little "tink, tink, tink" from that as well. No amount of fan swapping with identical fans was going to fix that, as it was not the fault of the fan itself, but ( IN MY OPINION ) a result of using the wrong fans for the space alloted.
To replace the fans, I decided to try a MagLev fan ( magnetic levitation), which I found out about thanks to cpr4cpu on another aquarium plant message board.I found the fans here,
but it looks like they are out of stock. The stock number has changed as well, since the part and manufacturing number was 997-0029 and KDE1205PFV1 MS.G. It wasn't easy finding the right size in a MagLev because 50mm isn't the most popular fan size to begin with. For someone just wanting to fix the immediate problem with the fixture, however, any 50mm x 50mm x 10mm fan should work just fine as long as it is 12 volt DC and .12A or 1.4W. The thickness of the original fans is the main problem.
The below pictures should illustrate the difference in thickness.
I took the end of the fixture off with a small screwdriver ( NO POWER TOOLS - stripping the screws is the last thing you need) and clipped the power lines to the fan after determining the length I needed them to be based on how much the new fans came with. The new fans came with bare leads and I thought about putting the 2 socket plug on the end , but my fat fingers couldn't pull the plugs out of the fixture, so I decided to just clip and solder. The picture was taken on the tank so I could get a better shot. You don't want to do the actual work on it while it's over the tank.
After that, I just unscrewed all the old fans, making sure to keep the three sets of power cords separate from eachother, so I'd know what pair of red and black wires went together. A quick strip of electrical tape to keep the pairs together before clipping is ideal.
All I did was solder the power cords to the leads on the fan after stripping the wires, wrap each wire individually with high grade electrical tape, then wrap the two wires for each fan together with the tape. I thought about using a variety of different connectors instead of soldering as well, but the limited room inside the fixture lead me to believe it would cause a problem. The electrical heat shrink I was going to use was woefully too small, otherwise a nice length of it around the electrically taped parts would have made a nice addition as well.
I went to install the fans, and realized there was no way the old screws holding the fans in place would work. They were way too long for the new fans. After going all over town with the end of the fixture, a new fan, and a screwdriver in hand, I finally found some screws that worked perfectly at Lowe's home improvement. They were 4 x 1/2 Pan Phillips Zinc screws, for sheet metal. I also found that the way the fans wanted to go in ( they fit perfectly with the grooves!) was not the correct way, but it still seemed to push a whole lot of hot air out of the fixture, so I was tempted to leave it that way, shown below.
I ended up flipping them around the correct way, so they would be sucking air through the fixture instead of pushing it. It didn't take up that much more room inside, and the same screws I found still worked fine.
From there, I just used the electrical tape to corral the fan power lines, shoved them into the little space where they go, and put the end back on, making sure the cords weren't in places they shouldn't be.
Days later, I am still enjoying the quiet fans. They're too thin to rub against anything and run quieter than the original fans, rubbing or obstructions aside.
If anyone picks up these fans where I got them, should they get more in, I should note that I thought it was lame that you have to put in your credit card info before you can shoose shipping, and you don't get a total until they ship, but I can tell you that three fans shipped from their Texas warehouse to North Carolina is $9.76 for shipping . Three fans with shipping cost me $24.70. In the drop-down menu, be sure to choose 'Groundtrack", which is UPS ground, and the cheapest method they list.
For anyone wanting to find this exact fan elsewhere, they are 50x50x10mm Sunon fans, 12 volt, manf# KDE1205PFV1 MS.G . They will work with the exact jbj fixture I indicated, but I doubt they'd work with all of the models. They are 1.4 watt, 12 volt DC. The original fans in this fixture are 50x50x way more than 10mm, , 12 volt DC, and 0.12A . I believed them to be similar since 0.12 Amps x 12 volt = 1.44 watts.
I just wanted to post this in case anyone else was having the same problem. I had bought these lights for $150 something from a place that was having a sale, and was totally and completely bummed about this problem. I spent two days searching for the right fan and most of a day just finding the right screws, so hopefully this short article finds someone else with the same fixture and saves some time and grief.
I'm not an electrician by trade, nor a die hard DIY'er, so if anyone can point out a better or safer way of doing this ( i.e. specific connector instead of soldering, etc.), then by all means please share.