Fluorex fluorescent - First impressions

[donjasper]

A company called Lighting of America produces a florescent flood light using a ‘Fluorex’ fluorescent bulb rated at 65 W, 6500K and 6,825 'brightness' lumens. 10,000 hour bulb life. Those are the numbers on the box. (Salt is not included.) You can pick one up at a local Home Depot for about $30. (I bought two). Replacement bulbs were around $27.
These babies are not for everyone. If you don't know when wire nuts are in season - pass these up. But if you've changed a receptacle in your house or managed to do a little bit of around the house wiring without a fatality - then you should be able to manage a DYI project with these things.
Ok, so I bought two. They are packed in a plastic housing roughly 12" by 8", with a clear lens. They have a metal reflector (unenthusiastically painted white). For my application I wanted to install them in a DYI aquarium hood (screwed to the lid). So I removed the lens and 'altered' the plastic housing to make it smaller. You don't need to go to the trouble that I did to make them fit, but I wanted enough empty space for two more over my 30 gal (when the time comes) $$$. I'd rather buy critters than light fixtures.
Ok, they are nearly absolutely quiet - and they are bright with no sign of the ‘yellowish’ tinge to the light. I've got them about three or four inches above my water level (Metal Hydride guys eat your heart out!) I'm hoping to be able to get some sps coral happy, right below the water line directly underneath them. (Ok so MH has lumens to spare and can deal with the intensity falling off with the square of the distance thing).
If anyone is interested I'll be happy to post periodic updates as I find out what livestock likes them and how they age.

 

[jarvis]

I wouldnt try to keep any corals under that light especialy SPS. You might be able to do alright with some corals if you can replace the bulbs with ones for designed for reef tanks. I also belive people use these ones to light a fuge and there is some modifications that you need to make so they dont over heat, and posibbly a small fan to keep the temp down in the tank. I hate to bring more bad news, but the ballast could be magnetic vs electronic ballasts in which case would lead to shorter bulb life. The bulbs are not that cheap either.

 

[donjasper]

The ballasts are electronic (if they're in the housing). I was rather unimpressed - a small circuit board about the size of the palm of your hand made up of mostly empty space. I figure that the ballasts are probably inside the bulbs themselves - like the fluorescent bulbs they make to replace incandescent bulbs. That’s the appearance of the bulbs anyway – a very large incandescent replacement bulb.
I'm not done with the project yet and I've plans to put a layer of clean glass on the bottom of the hood/top of the tank. Mostly to keep stuff for falling into the tank without authorization. I'm kinda hoping that they are able to keep the tank warm - maybe the waste heat from the lights will help the heater run less.
I'm not all that worried about the temperature damaging the bulbs, after all they're made to operate inside the plastic housing sealed with the clean lens. And after my (ah hem) mods - the clear lens was the first to go. (Whacked off the top too to make the things fit cross-wise in the hood, but like I said – not everyone would want to do that). I'm ready to add a small fan if I'm not happy with the temperature inside the hood.
I'm not sure how to respond to your observation about the replacement bulb costs. If that's your opinion - you're welcome to it. If you think I made a factual errors and that they're actually more than $27 - well that's what my local Home Depot sells them for. I’m more worried that (if these things do last 10,000 hours) that in three years the company will have either gone out of business or will have stopped making them.

 

[jarvis]

Generally its not a good idea to have an enclosed glass top on the tank due to lack of gas exchange and heat build up. A stable temp is the most important thing. Well you do have an electonic ballast which is a good thing. Even though the bulbs say they will work for X number of hours the spectrum is not designed for aqauria use. It will most likely grow plants and algea pretty good. Not exactly what you want to achive in a reef tank. Even though PC or VHO bulbs have a recomended life expectancy of 9 months to a year depending on who you ask it does not burn out so to speak it just seems that the spectrum shifts and the output of LUX is dramaticly lost rendering them useless for coral growth in most aspects. I would post a pic or describe the style (ie square, round, placement) of the pins to see if you can get a bulbs to match up with the socket.

 

[donjasper]

Well this could probably fit under another thread call 'DIY Reflectors', but I clearly decided against it.
Ok, so I happened to have a mirror around the house and I want to get as much light out of these bulbs as I can. My better half has a expensive photographic light meter than can read foot-candles, so armed with that I laid the hood on it back (pointing up) and began. Shedding some light on my methods I took all the readings 12" from the bulbs. Many manufacturers list the output of their bulbs as the total output in all directions - which clearly isn't useful to those of us that want the light going in roughly one direction.
The baseline configuration was simply removing the bulbs from their housings and laying them on the hood material (MDF sometimes called partial board). I took a light reading. Then I placed the mirror between the bulbs and the MDF. The readings promptly went down. Not what I was looking for! Reflecting on what I saw - I noticed that the mirror spent most of it's effort reflecting the ceiling of the garage. The surface of the MDF would have a speckled appearance, as some of the wood chips would bounce the light trying to leave town back into my eye (or light meter) whatever. The mirror was great reflecting the light back into the bulb - where it never was seen again - or in any direction other than up.
I recalled reading that the most efficient reflector is an M shape like the McDonalds arch - with the light at the point of the M. So that even the light emitted backwards gets reflected around the bulb and out. I wasn't about to McDo that.
Determined to make some use of the mirror I got the bright idea to see if I could improve the reflector. Using only the MDF as a reflector I got a reading of 3,610 lumens. Using the painted white reflector the came with the lamp I read 5,550 lumens. I then used a glass cutter and cut the mirror into 2 pieces 3.25" by 7.75" and fit them into the plastic house. Of all the bad luck - the readings went down again. But I began to see the light at the end of the tunnel - for I realized that what I wanted to see in the mirrors was the bulb itself. Repositioning them lead to a single bulb reading of 8,250 lumen.
So I cut two more pieces and did the same with the other housing. And started using the lights in combination (remember that I bought two of them) - with the bulbs 7" apart. Using the painted reflectors - which are a pretty good reflector all in all - I had a combined reading of something like 6,660 lumen. The brightest readers will notice that two bulbs don't double the output - there's some science here that I don't understand. Could be the distance squared thing - as the light from the second bulb has to travel farther. Using the two bulbs with mirror reflectors made an impression even before the reading was taken - the environment was distinctly unpleasant. And after blinking away the spots in my eyes enough to read the meter - got a reading of 11,000 lumens.
The final configuration has the follwing characteristics: The light emitted in the opposite direction is lost. It hits the housing and some is bounced into the bulb - they are compact bulbs that measure about 3" across - with four 'loops' of glass tube. However light emitted to the sides hits the mirror(s) and is reflected down. The light emitted down is left to carry on.
The output using two bulbs with white reflectors went up some 20% over that of a single bulb. The combination with mirrors led to a 33% increase. I cannot explain this - perhaps unenthusiastic meter reading, perhaps some math thing that I don't really understand.
The mirror is a standard household mirror - was about 3' by 3'. Scoring the glass through the reflective layer on the back was not a good idea. Scoring the glass on the front lead to very desirable results. I used 'running pliers' to start the crack forming, but slow even pressure would work. (I wanted to make sure that I had enough of the mirror left to put behind my aquarium and making a 3 foot long cut is tough in the best of circumstances) Using a smaller mirror would be recommended.