Metal Halide Q&A

Oh, ok that shouldn't be a problem. I just don't want my canopy to be too tall but even if it's 12" high to keep the bulbs at 10"+ from the tank. I will be incorporating 2 or 3 fans into it also.

 

MH watts

You don't list a 150 watt MH. Is there a reason?

Also Glass canopy with MH (Y/N)? Will the thickness of a glass canopy reduce the "effectivity" of MH? Or more appropiately will increased thickness reduce the "effectivity" of MH?

Thanks - Great discussion.

 

150watt is very similar to 175

Yes, glass will effect mh... It effectively filters out the short wavelength, high frequency light (UVA, UVB, UVC). The thicker it is the more of this light is lost. Typically a thin piece of glass is used to stop wavelengths below 300nm, however I have seen some amazing tanks where there is no glass shielding!

 

If its growth that you are looking for a 10K is not all that great as a trade off in a system I would consider a pleasure hobby tank and worrying about the pure aesthetics of the tank. I get good growth with my 20K as good as I do with cooler lamps on the commercial grow out troughs . But if its growth that you want then a 55 or 65K is the bulbs as that is burning at the same lengths a natural sun coral will just look brown ..
Unless you have a deep enough tank like 10 -15 ft or so to pull out the yellow and red wave lengths to get the Higher K values from the sun or cool K lamps . As for the actinic needed or not I get to run my M/H 6 hrs aday and I run the 03 UVL VHO's for 6:30 am till 10:00 PM cheaper to run and corals all have great coloration and they grow out well with all the actinic.
We has several clinets with tanks 10 plus foot deep ran 1000 W 10K and VHO actinics and they did great had yellow tangs even spawing in one of them corals up hig and on the bottom all did very well .

I have ran 175 and 250 M/H on many stock factory hood like from All Glass they classic oak design models and lamps ? 6" maybe a little less off the water . This all depenes on the type of cooling fans and how they are set up and the CFM ratings of the fans and you just have to be sure there will be no water splashing onto the lamps .. I ran a 90 here and in va with 3 250 here and 3 175's in Va all on the same hood with proper 4" fans and never a problem . And if you use a chiller its never a issue other then water hitting the hot lamps . And if you use M/H and do not keep the ambient temps of the room in the low 70's and humidity less then 55% to increase evaporation then the tank will heat up anyways fans or no fans big or little .

 

I'm building a 80g tank right now. I've got 3 250w moguls. I'm planning on only using two in a hanging canopy. What distance from the water should they be? The tank is 24" deep and has 6mm thick eurobracing

 

With only being 24" deep you can put them any distance you want... you will get plenty of PAR anywhere in the tank with 250's

do you have a ballast and bulb preference

 

They're Hamilton ballasts at the moment. Got a sweet deal on CL. I do plan on upgrading to Icecaps if I run in to any issues. I'm clueless on the bulbs at the moment. The ones that were included look at bit old and are 14k. Any suggestions? I will also be supplementing with t5 actinics.

 

The icecap will be nice!
Good bulbs are:
Iwasaki, South Pacific Sun (I like these a lot, so does Tangster), Ushio, Phoenix, and XM are all good ones. Reeflux has nice color but they go bad faster than others.

If you want data like PAR, color temperature, efficiency, or a plot I can help you out

 

I'd ask what type reflectors and lamps are you going to be using ? They are more important then many think all are not equal, I have some that would make a 175 w do more then a 250 with a lesser type.. If you have just the simple 1/2 U shaped parabolic then I'd say 10" tops Hamilton's simply use the Magnatek or Advance Iron core ballast I have replaced a ton of them in their little boxes . It will do fine thats all the ballast/transformers I ever ran , I have ran many test using one or the other and there are just to many variables to say this one is better then that one . The electronics are a little better and more efficient but a 35.00 one like I run last 20 yrs and I have never had a electronic to last all that long.

 

Too bad the MH waste so much power as heat, otherwise with those peaks at 420, 540 and 580, the 10,000K MH would definitely be the one-stop-shop..