Power Compacts(PC)/Compact Florescents Questions

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Dec 17, 2003
1) PC vs. Standard Flourescent Wattage and Light Output:
I've heard PC wattage output of 55 watts is "equivilent" to a VHO @ 95 watts. I've also heard that PC light output is "3.6 times" that of a standard fluorescent bulb.

a) Does anyone know what the actual wattage/light output comparison/conversion is when comparing PC to standard flourescents?

2) Quality of PC Light:
I've heard that the PC 7100K Actinic blue is not a true actinic. I also read that PC lamps do not have the same "glow" VHO puts off which may contribute to algae problems.

I don't know if my information is out of date or not...

a) Does anyone know if the PC 7100K Actinic blue is or is not a true actinic? (Why does it matter if it isn't?)
b) Can anyone comment about the different "glow" and possible algae problems?
c) Any reason why I shouldn't be considering PC lighting as part of a lighting solution for a planned 150 gallon reef tank?

Thanks in advance for any comments and/or replies.....


Evil Genius
Jun 30, 2003
Sultan, Wa
For what its worth, this is my first hand observations after running PC lighting over my 135 reef for the last 5 years.

I've run 4 x 96 watt bulbs of various spectrum frequencies, and have never owned VHO so sorry, I can't compare the two bulb types.

My tank is a plexiglass with a shorter 5-6" tall hood, so PC lighting works well to keep heat down, and the 36" long 96 watt bulbs fit the 6' long tank perfect in a 2 wide, 2 deep bulb arrangement.

Year ago I believe I started with 5500k, then 6700k mixed with the old style 7100K, and have now stepped up to 10K bulbs.
The older style of actinic wasn't a true type, but I believe newer styles such as a smart bulb do radiate a true actinic spectrum. That said, I'm presently running 2 x 96 watt 10K bulbs, and 2 smart bulbs, (which have both 7100K and 10K side by side in the same dual tube bulb). I'll most likely just run all 10K bulbs in the future for a whiter light when I replace them next time.

I tend to replace them every christmas (makes a nice present to myself) but I've also ran them 14-16 months but they do start to shift yellower. Algae isn't a problem at any time with the bulbs, regardless of their life-span.

Note: I run a mix of SPS and softies under the bulbs, and both seem to thrive well. I run the PC's simply for the lower heat output, as halides would get to warm with the plexiglass tank, but if I had to do it over again I'd re-make a new hood and go with halides depending on what you're trying to keep in your tank.

96 watt PCs aren't cheap even mail-order, as they're $45-50 a bulb, so $200 a year just for bulbs isn't cheap when you're running 4 of them. You need a ballast for every bulb in my 96 watt arrangement, so thats not cheap either.

Good places to shop for the electronic ballasts/bulbs and more information on them are www.AHsupply.com, or www.marinedepot.com

Hope I helped shed "light" on the pro's/con's of PC lighting for you. PM me if you have any other questions.



Seeker of knowledge
Jan 8, 2004
I used 2x96W and 2x65W PC lights over my 40gal for about a year and a half, and although I can't compare them to VHO I would like to offer my two cents. I ran two actinics, one 50/50, and one 10,000K bulb (I really like the blue of the actinic).

I was very happy with this lighting setup, as were my clam, LPS corals, and soft corals. I experienced very good growth rates and reproducction, no problem algae, and the tank appeared visually bright with good coverage. They supposedly run pretty cool, but this must simple be by comparison because you will still want good hood ventilation.

I have since switched over to a 250watt DE HQI 10KK setup, and the corals *do* seem a little happier, at least the high-light ones and the few new SPS do. The coverage isn't as even, but the glitter lines look cool ;) I purchased this setup for about $350 or so, which is a little cheaper than the PC lights were, all told.


Well-known member
Jul 1, 2003
Issaquah, WA
You can now buy two actinic pc bulbs, one is the 7100K and the other is classified as a 03 true actinic. I started out with the 7100K and it is just a very blue bulb and not close to the actinic VHO. I now run the PC 03 actinics and find there color much more appealing and very close to the VHO version. With that said if I were to start over again I would go with the newer T5 bulbs.


Hermit D Crab
Nov 20, 2003
I have 1 T5 actinic I am testing out on my 46gallon before I resort to all actinic T5's to supplement the 2 250w MH I am builing for my 110 gallon. It is very blue and nice by itself but is easily over powered by the White T5 and I am concerned T5's will not provide enough blue to show up with the MH running.. Do you have any experience with T5 actinics looking good with MH... just curious.. (running 2 10000K XM 250w on electronic PFO ballast)