Curiousity questions about lighting...

[QCppg]

I have a few questions of mostly academic interest about some high powered lighting systems.

1: Why can't you use standard 175 watt mercury vapor lamps in concert with compact flourescent lamps for reef lighting? I was just wondering because they cost about $25 for a ballast and bulb, and $8 for a replacement bulb.

2: Are the 70 watt metal halides they sell at Lowes suitable for reef lighting with the ballast moved into a custom fixture (Cost around $65, manuf. by Reagent)

3: Is there any PRACTICAL way to spread the light from a single halide lamp across the width of a 55 gallon aquarium without elevating it greatly (since the power compact fixture prevents this)?

4: And just what is the difference between a metal halide ballast and other HID ballasts (Mercury or sodium)?

As I said these are mostly curiousity questions. Thanks.

 

[FL Knifemaker]

Very good questions. I look forward to hearing what the experts say.

I read on the other forums that mercury vapor doesn't put out the right type of light, wavelengths, etc. The one in my shop makes colors look strange as well.

 

[slipknottin]

1: Why can't you use standard 175 watt mercury vapor lamps in concert with compact flourescent lamps for reef lighting? I was just wondering because they cost about $25 for a ballast and bulb, and $8 for a replacement bulb.

MV bulbs usually have an undesirable color spectrum of under 5,000K.

2: Are the 70 watt metal halides they sell at Lowes suitable for reef lighting with the ballast moved into a custom fixture (Cost around $65, manuf. by Reagent)

The ballasts and fixtures will probably work fine, with some decent bulbs made for marine aquariums.

3: Is there any PRACTICAL way to spread the light from a single halide lamp across the width of a 55 gallon aquarium without elevating it greatly (since the power compact fixture prevents this)?

No. The max spread you can get is roughly 3'. And even then the sides will be significantly darker than the center.

4: And just what is the difference between a metal halide ballast and other HID ballasts (Mercury or sodium)?

Im not sure what your asking, are you asking how the ballasts function?

If your going for an inexpensive setup, you can actually use MV ballasts and run the 6,500K saki's.

Heres a little article with info on how the ballasts operate, if thats actually what you wanted to know- http://www.ecmweb.com/mag/electric_voltage_variations_arc/

 

[QCppg]

Thanks for your info. And yes I was looking for a way to build a cheapo halide fixture or equivelant. Not to mention that I want to keep the total system wattage below 500 watts (that's input power, not effective throughput). As to the question about the ballasts (question 4) I wanted to know if any of them were interchangable.

 

[slipknottin]

This article on 'MH for under $100' should show you how it could be done.

http://aquarium.union.rpi.edu/articles/DIY_MH.html

 

[QCppg]

Good link. With that info and the link to Premium Aquatics I could build a 70 or 175 watt fixture (I just plain don't need 250 watts since I plan to use this in combination with my 4x65 watt Power Compact). I could probaly put a single lamp near the center of the tank this way and still get a decent effect. Thanks again.

 

[FL Knifemaker]

Yes! Good link!!! Thanks

 

[dturano2005]

I have seen ballasts for $30-$40 which handle 220 wats.

Could I swap out my old ballast and and use two of these to creating a new VHO lighting system for my tank? The reason why I would use two is taht Im looking for a total of 440watts to power 4 110 watt bulbs for a FOWLR tank and then maybe upgrade to some coral?

Because right now I have a 4-40 watt bulb setup that wouldnt be suitable for my tank?