Halide Q & A

How close to the water should MH be mounted? I only have a 10" high canopy and am afraid that I will have to go with T5. I really like the look of the 250W Radiums 20K.
 
I am no expert, so take this with a grain of salt...

I have done a ton of reading since I started posting here and think I have a grasp (all be it a small one) on MHs. Distance is going to be based on a number of things, including tank depth (how deep your water is), strength of your halides, and quality of your reflectors. Something like lumenarcs or lumenbrights actually allow (and require) your lights to be higher away since they pump THAT MUCH MORE light into your system. As a guideline, I am looking at doing some DIY lumenarcs and am fairly certain that I can get at LEAST 95% of the "real thing" recreated. Honestly I am betting I can practically match it. I will end up mounting 2x 400w halides 16" above the water in a 24" tall (water depth) tank.

I don;t think there is any misinformation here, but anyone else who knows more than me, please do chime in.
 
Well, I didn't use any real formula as such but rather common sense. Since I have DIY Lumenarcs (or brights...I forget which style I made ;-) I wanted to just be sure I had plenty of space to get under them for feeding, maintenance, etc.. Some people have gone all out and made tracks to slide their canopies back out of the way but I didn't feel like going through all that. I have around 11-12" under my glass splash shield (1/4" plate glass) and that seems to be a pretty good height. Over the shield I have about a 1/2" gap for air flow and then the bottom edge of the reflectors.
 
I would be interested to see par reading of your tank in various spots. The info I got was from melev's reef. He used to go 12" and went 16" when he switched to the lumenbrights based on PAR. Maybe someday I will splurge and spend the cash on a cheaper PAR meter...

By the way, if you crafted your reflectors with the template you linked, those are lumenarcs :) The difference is that the brights keep a hexagonal shape throughout, whereas the arcs "turn into" a square at the bottom. The brights reflect 16% more light (supposedly), but with the INSANE amount of light increase we already get from these things I doubt it matters too much unless you are using really low wattage lights and just want more out of them. If I could find a lumenbright template though I would be game for giving it a shot. A few more bends and rivets is the only build difference. Maybe I will try to see if there is a CAD program at ISU that I can go and use >.>
 
Yeah, arcs, brights...I get them confused as I didn't care too much either way since I don't have a reef. Mine are square at the bottom so mine are arcs I guess. I've only seen templates and threads for the style I have. I've read some who say the hammered metal really makes a big difference over the mirrored aluminum in terms of a more even light dispersion so maybe that would be an option to check out as well.
 
I honestly think that is just preference. I only say this because based on people's PAR rating, lumenbright has been the best model of reflector, and that has no hammered metal whatsoever. I just got the materials to make two large reflectors. Only cost 44 bucks at menard's plus 5 bucks in rivets. Gonna make some and post them up here when I get a chance/
 
Here are my reflectors. Turned out really nice. Still need to remove the blue protective film and fit the sockets in :)

IMG_0085.jpg
 
Just got my plusright bulbs in. Testing them out now. First impression is... I just saved a ton of cash and I am liking what I see :)
 
I have 2 250w 14000K on a 120g 48x24x24 plus i also put 2 coral life blue T12 but my fish say hiden and corals stay closed lights are about 7" off top of water stared at 2 feet off and still no love can anyone help!!!!!!
 
Lord, nice pics and the reflectors look good. I added the bends at the bottom of the reflectors to keep the metal straight but that's just cosmetic. Mine still look ghetto as I have no sheetmetal skills whatsoever. :)

Johnnie, maybe your problems aren't from the lights? What about other environmental conditions or water chemistry/quality? Give a few more details on your recent changes and maybe something will be revealed. I think your MH wattage is reasonable for your tank height. You also could mention what type of bulbs you are using as well as the ballast. Do they look very bright when fully warmed up? How old are the bulbs?
 
my MH are coral vue they light up bright then turn a blueish.I just changed from a 85g to this 120g i used same water and everything let run for 3 days befor I put anything in it .tested waterand it was good nitrite was a little high 1.0
 
That much nitrite could be your issue. You shouldn't have any nitrite registering. While it may not be lethal just yet, sustained exposure could cause issues, especially stress, which is what you are experiencing. I suggest you either do a large water change or maybe get some of the instant bacteria products out there (or do both steps). I used Seachem Stability when I started my tank and had fish in 3 days after and ever since. There are other similar products and they all add nitrifying bacteria to your tank to quickly cycle the nitrite out.
 
too much light?

too much light?

i have a huge delema on my 46 gal bowfront there is a center brace which i believe is just to support the glass top...so i replaced the glass top with egg crate but the brace is still there i want to get my lighting system that is either going to be (two MH on the sides between to power compacts) if not that then the single MH in the center which will get shadowed by brace with 2 power compacts
 
ya I was going to do a mager water change I also put some AmQuel+ removes nitrate& nitrite plus ammonia chlorine and chloramines. BUT now some of my fish look like someone has eaten they're tail fins what should I do? even my tang has spots and hasn't eaten and on top of every thing els now I'm seeing these worms in my tank I think they are bristle worms have no idea how they got in there or what to do about them I know I DON'T like them!!
 
Last edited:
rguyler said:
Lord, nice pics and the reflectors look good. I added the bends at the bottom of the reflectors to keep the metal straight but that's just cosmetic. Mine still look ghetto as I have no sheetmetal skills whatsoever. :)

Johnnie, maybe your problems aren't from the lights? What about other environmental conditions or water chemistry/quality? Give a few more details on your recent changes and maybe something will be revealed. I think your MH wattage is reasonable for your tank height. You also could mention what type of bulbs you are using as well as the ballast. Do they look very bright when fully warmed up? How old are the bulbs?
Click to expand...

I might end up doing those bend but I didn't know how to do them right. If you can believe I did all of those bending by hand using a metal ruler... LOL
 
slick6669 said:
i have a huge delema on my 46 gal bowfront there is a center brace which i believe is just to support the glass top...so i replaced the glass top with egg crate but the brace is still there i want to get my lighting system that is either going to be (two MH on the sides between to power compacts) if not that then the single MH in the center which will get shadowed by brace with 2 power compacts
Click to expand...

When the MH is raised to the proper height, there is actually very little shadow. You might get slight shadowing at the very top of the water level but not too bad. DO NOT remove that brace. It is there as structural support for the tank. Without it, you may have the glass blow or the seals weaken.
 
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