Which is the coolest Metal Halide?

Mogul's are single ended and have the UV shield built in and HQI is usually used when referring to double ended bulbs which will NEED a UV shield. For the most part there is more k options and manufactors for SE bulbs than DE bulbs but that is slowly changing. Which is better, well many people argue either way.... Many times it boils down to the wattage needed or the fixture preference of the user.

Happy lighting!

 

I am lost when it comes to electricity. This is going to sound stupid what is the purpose of the UV shield? Is it a built-in reflecter? Does it give off more light? Sorry for these rediculous questions.

 

the UV shield is just a piece of glass covering the area that the light is in. it doubles as a splash guard.

 

Metal halides emit ultraviolet light as part of their normal spectrum. UV light is dangerous to our eyes, and to some surfaces; hence the necessity for a shield to block it. As one poster mentioned, mogul (screw-in) halides contain this shield in the glass capsule, HQI's don't, and need a UV lens.

All good questions.

 

Wow! I"ve learned a lot in one day...

 

The U/V shield on a HQI is more then a splash guard its a U/V filter if that ever brakes or a Mogul ever crack and keeps firing and I have seen them do that many times then all the corals near and under that will be burned up and radiated to death. I myself use 3 400 Watt on this 90 gal . 400 watt Moguls I do have a chiller and adding one lamp will do little for lighting it unless its a small tank and you want to keep simple corals ? Like leathers and stars and stuff like that ?

 

There's no such thing as a cool metal halide. They're all hot as heck, although you can minimize the heat by running an open top, and using a small fan blowing over the surface of the tank. My tank stays around 80 degrees, 81 tops with the MH and fans. If you use a canopy, you will most likely need a chiller.

Don't remove the UV shield, if water hits the bulb, the bulb will burst. UV light is also harmful to your tank and your corals and fish could sunburn, not to mention it's not good for your eyes.

Even though my tank stays around 80-81 I will be obtaining a chiller soon as it's not summer yet and the temp is already at the max.

 

MH and heat

IMO. The more watts the bulbs are, the more heat they will put out.

And you don't have any MH in your system now right? So adding any MH that's 250w or more will increase your heat output.. I would say 1w per gal..so one 250w bulb would increase your tank temps by 1. You said it may go to 81, so it may goto 82 after just one 250w bulb. 81 from what i've been reading is too hot. I think before adding MH you should get a chiller...then no more worries about heat and you could put in 2 400w MH's knowing you have the gear to take down heat if need be.

Thanks for reading,
Mike

EDIT:
OH you live in FL,,yes get a chiller summer coming.
And if you only want it more bluish use 7100k/460nm blue lights, put a few of them in there..BAM more bluish

 

There are several ways to manage your water temps. Water cascading into your sump has an evaporative cooling effect. Having an open top tank does wonders. Using an inline pump instead of a submersible is good too. Lastly is the proximity of the lights to the water's surface.

I live about 10 minutes from you, Marlinman, in sunny Florida. I currently have have 2x150 halides. My water has yet to exceed 80 degrees. I'm planning on upgrading my 2 150's to 2x250's soon. I don't expect to need a chiller.

I wouldn't recommend such an expensive preventive measure until you have confirmed that it's necessary, but that's just me.

 

Warming up?

True, a "chiller" is a bit of money
Other units would cool the water, like a water cooler.

A good defense is the best offense,
Mike