Metal Halide vs PC bulbs

[nighthawk]

Okay, maybe this has been covered before, and if so someone can just point me to where it's posted.

Here's the question: Is there any real necessity for MH lighting if you can attain the same or close to the same amount of wattage using PC bulbs? Is there a certain wavelength or sprectrum that the MHs produce that are clearly better than what you can attain in PCs?

I've seen several systems that I'm looking at purchasing, 1 a MH and flourescent with a wattage of 560, and another that is 4 PC bulbs with a wattage of 520. Both will give me around 7-7.5 wpg for my75g tank (I'm assuming that this is considered moderately high wattage? At least for inverts and a few corals evetually?). So what is the real difference in these systems, other than an extra $150 for MHs. I'm guessing there's something that I don't know about, or is this just a preference of the individual aquarist?


Thanks for the help

[bigdscobra]

Dont know the actuall difference but from experience and starting off with dual 96w =192w PC on my tank, than going to a 175w MH with VHOs actinics made a HUGE difference. Everything seemed like it grew overnight, and with the MH you can keep any kinda of corals you want and not worry about light. I now even upgrated to a 250w MH and wont go back to the PCs. IMO its worth the money, you can get ballast and reflectors and piece your own MH set up together for alot cheeper.

[brewercm]

Man, that's an open question that can have a thread go on forever. :D

The easiest answer is that it's more about PAR than about Watts per gallon. Here is a link to a great site that will give you more info than you probably ever wanted. Go into the articles section and look around.

BTW, of the lighting available, Metal Halide, T5, Power Compact, VHO, the power compact is considered the least desireable of the bunch available any more. Granted this is just in general and all things in this hobby tend to swing back and forth with the wind. :roll

Oops, forgot the link originally. Here you go.

http://www.reeflightinginfo.arvixe.com/#

[alton]

Metal halide is cheaper 2 -250w MH lamps $120 / 8 - 65w PC $240 Replacement cost. The color of your fish and corals Priceless. I have used PC since they where introduced and have had great success. But MH is better. Foot candle readings for a comparison 2 - 250w MH 14 K lamps 2,500 Ft. candles verses my old setup of 8 x 65w PC 1,500 Ft. candles.

[nighthawk]

Thanks for all the quick responses.

The thing that I was looking at was the new 130 watt PC bulbs that are just hitting the market.

So the main difference between all the bulb types (MH, T-5, VHO, PC, etc.) is the K rating that the output? I'll take a look at some of those articles.

Also, my needs may not require MHs. My plan is to house inverts and break into primarily the soft corals. From what I've read I shouldn't really need any kind of super intense lighting. I'll have to look into piecing parts out to make the MHs.

[bigdscobra]

Advanced magnatic ballast from an electric supply place 250w $40-50, Retro fit reflector with socet $20 XM 20k Bulb $65 Just some basic wiring and your done. ;) it is well worth it you will notice better growth in softies with the MH light too.

[Pacman]

Ok, gotta throw another idea at you if that's ok. If you plan on starting with just softies, you may consider getting an Ice Cap 660 VHO ballast and 4 bulbs for the 75. It's a great lighting option for softies - not too intense, with good colors and growth. Also, if you decide to upgrade to MH in the future, you'll already have the VHO's for actinic supplementation.

[GaryP]

Metal halide is cheaper 2 -250w MH lamps $120 / 8 - 65w PC $240 Replacement cost. The color of your fish and corals Priceless. I have used PC since they where introduced and have had great success. But MH is better. Foot candle readings for a comparison 2 - 250w MH 14 K lamps 2,500 Ft. candles verses my old setup of 8 x 65w PC 1,500 Ft. candles.

What he said.

In case some of you don't know alton, he does commercial lighting for a living. He knows all that foot candle stuff. I'm going to get him to design the lasers for my new tank. :)

[gjuarez]

Okay, maybe this has been covered before, and if so someone can just point me to where it's posted.

Here's the question: Is there any real necessity for MH lighting if you can attain the same or close to the same amount of wattage using PC bulbs? Is there a certain wavelength or sprectrum that the MHs produce that are clearly better than what you can attain in PCs?


Thanks for the help

In my opinion, using watts per gallon is not a good way to measure lighting needed. The most important thing in determining what lighting you need is to know what you will be keeping? The type of corals as well, lyke softies, lps or sps. PCs would be my last option. I like t5 and vho as far as fluroscent. My first choice would definately be Metal Halide, unless it was a fowlr setup.

[1460sun]

Metal halide is cheaper 2 -250w MH lamps $120 / 8 - 65w PC $240 Replacement cost. The color of your fish and corals Priceless. I have used PC since they where introduced and have had great success. But MH is better. Foot candle readings for a comparison 2 - 250w MH 14 K lamps 2,500 Ft. candles verses my old setup of 8 x 65w PC 1,500 Ft. candles.

What about the cost difference of running the MH vs. VHO's (lets say T5's). My electric bill is 3x what it was last year at this time and lets face it the more I spend on untilities the less I have to spend on the things I want. So I'd be willing to pay more for the bulbs if I could get the same or near the same light.

[alton]

What gets expensive with MH is when you purchase old ballst that are no longer efficient. As ballast get older they lose there life, there fore they start getting hotter and as anything gets hotter it uses more energy. Some new electronic ballast claim 100% efficient. I don't quite believe that so let's reduce that to around 95%. 250w / .95= 263 input watts versues an old mag 250w / .75 = 333 input watts. Major companies are changing out there old mag ballast for new electronic and are claiming they will pay for themselves in 3 to 5 years in energy savings. Remember not only are you saving energy on ballast usage but on heat from the ballast. 263watts x 2 lights x 10 hrs a day x30 days a month = 157,800 watt hours / 1,000 = 157.8 KWH x 10 cents = $15.78 a month and $189.36 a year for 2 - 250MH with electronic ballast / Old ballast 333 input watts same formula = $19.98 a month x 12 = $239.76 a year

[1460sun]

Great info thanks. Guess I need to look in another direction for the huge increase in my electric bill since my ARO ballasts are electronic and I'm not evern running the VHO's 10 hours a day.

[hobogato]

my bills increased alot this year, mostly because of peak season and fuel surcharges. check your statement, it might help.

[alton]

Fuel surcharge raised my bill 30% during the summer

[1460sun]

I'm talking and average electric bill of $150 last year for Nov, Dec and Jan. In Nov it almost doubled and the Dec bill is 2.5x/3x more this year. Can't wait for spring/summer and the air conditioner to kick in. Yikes! There have been some slight increases in surcharges and fuel costs that of course have to be passed on to the customers but not enough to explain the difference. I was looking hard at the MH, since they are really the only difference. Altons post kind of rules them out.Glad that there not the problem, as I'd hate to go back to VHOs

[Bill S]

I have that same problem. Of course, it doesn't hurt to be married to Mrs. Griswold. I just bought her 24,000 more lights that were on sale after xmas at Walgreens!