Which gives me more light for the electricity dollar?

[capman]

I am a big facn of metal halides (I currently am using 400W metal halides) but I am contemplating lighting for a tank in a place where I am much more concerned about the electric bill.

Which will give me more light overall, and which will give me more light per dollar spent on electricity.....a 175 W metal halide (running on an IceCap electronic ballast) or four 4 foot VHO's (running on an IceCap or URI ballast)?

My bias is always toward the metal halides, but I'm guessing that in this case I might be better off going with the VHO's. This is for a 40 breeder reef tank with misc corals and either a bubble tip or long-tentacle anemone (Macrodactyla) by the way.

[yardboy]

Cap, I'll put my $0.02 in here. I use PC's , in addition to 250W MH, and though I've never used VHO's, the ads say that watt for watt PC's are brighter than VHO's. Notice I said the ads say that. I've also heard that t-5's are even brighter watt for watt, and that LED's are the brightest, watt for watt. Of course, t-5's are also darn expensive, and LED's are even worse (that is, to purchase)
Maybe I was overestimating the value of my info. It may only be worth $0.01.

[Doug1]

watt for watt I believe the Metal Halide produces the most PAR
I personally like the fact that you can overdrive NO bulbs with an electronic VHO ballast

[Geoff]

the undisputed winner in the watt to watt will be the LED's. unfortunately they are in thier infancy right now, so prices are insane on them. i think it will be a matter of time before we start seeing lighting manufacturers selling them. it still may be a couple to 5 years away though.

i also agree that the MH's produce the most light per watt. have not data to suport this so take this also as my .01.

G~

[tdwyatt]

Originally posted by Doug1
watt for watt I believe the Metal Halide produces the most PAR
I personally like the fact that you can overdrive NO bulbs with an electronic VHO ballast

more specifically the iwasaki bulb on icecaps or the HQI set up in terms of total usable PAR for corals. Search the net for Sanjay Yoshi and medal halide comparisons.

[Mafiaman]

Having just added two 250w MH (microwave halids "pun")
to go ontop of 768w of VHO two thing.
Firts one addresses your point the 780w of VHO used some juice but when I lit up the two 250w MH I could hear my meter. Sounded like a jet warming up LOL

But now the I've done it the MH do a few things that add to aqurium esthetics the light spot lights and reflects the water movment on the bottom looking alot like a sea bottom.

Also I just got thank you cards fro a few of my tank occupants. LOL

this didnt help much did it