Question about reflectors

[Stargazer]

Recently discovered this board and have already found it interesting and informative. My question is this. I have a polished reflector on my fluorescent strip light with 2 30W bulbs in it. Approximately how many watts does this equal out to if I had no reflector?

[m.lemay]

First off, welcome to the board!
I'm not sure I understand the question,but I'll try to answer it the best I can. Reflector or no reflector you would have 60 watts. when we talk about watts per gallon on this board, we assume that they have reflectors. 60 watts of light with no reflector would probably be closer to 40 watts of reflected light.
Heres the bottom line. Theres no getting around how many watts your plants need to thrive. There are no loopholes when it comes to growing plants, either the plants get what they need or they'll protest by slowly dieing.

[GulfCoastAquarian]

Marcel is right, and in addition, there are a lot of different reflectors out there. Some parabolic units reflect up to 98% of the light down. A flat piece of polished aluminum will only reflect 55%-65% into your tank (only slightly better than no reflector at all). An reflector shape isn't the only variable affecting useable light - the distance from the bulb to the reflector must also be optimal.

Short answer is: It's nearly impossible to put a number on it. But without a reflector, you'd only using around 30 watts of the 60 watts you were using.

[SNPiccolo5]

Flat piece reflectors are taht inefficient? I might look at getting some of those reflectors from AH Supply that are shaped to reflect more light....

-Tim

[Rex Grigg]

Don't forget that the AH supply reflectors are made for CF bulbs. Not sure how they would work with anything else. I know I have a 65 watt CF bulb in one tank with a flat reflector and you can look at it without pain. My 55 watt bulbs with AH Supply reflectors you can look at for maybe 3-4 seconds.

[SNPiccolo5]

I would end up retrofitting them into my 2x55 watt strip. Rex, can you tell much of a difference in the brightness of the tank from one strip to the other if they are on one at a time?

-Tim

[Rex Grigg]

Yes.

[GulfCoastAquarian]

I definitely can. I've got two strips over my tank (one with two four foot 40w tubes, and one with the two 65w PC's) and one has an angled reflector (CSL) and one is flat polished aluminum. The difference is just as Rex said it to be - you cannot stare at a pair of PC's under a parabolic reflector for anything more than a few seconds.

Reflectors are definitely a neglected topic in planted aquaria. We just pump in the wattage for more plant growth. Think of the electricity you'll save in the end with an efficient reflector. I've got to replace my flat one with a good one.