Help with new halide rig

[Tink]

So I'm getting hung up with the lighting plans for my new 180 build.

 

My fish room has a ceiling height of 7', and I'll be using an older 125 as a sump (72x18x22, only 1 center brace). The trouble this creates is a close balancing act when it comes to stand height (every inch shorter gives me that much smaller of a gap between the 125 sump top trim and the stand structure, but then every inch taller a bit more room is gained).

 

What this comes down to is planing to give myself the proper distance between the ceiling and the tank to accommodate my metal halides. I currently have LumenBright Mini reflectors to use, but am not married to them if there is a better option that fits. I plan to use either 250w or 400w Radium bulbs ( I like that 400 Radium color, but realize I may not have the height to run them safely/effectively ??) and just need to figure out the best space to have so that I can start planing my stand.

 

So my questions are these:

 

250 or 400 on my 180? Why?

Which reflector would best serve my needs (least distance between water and reflector, but still put out efficient PAR numbers)?

Optimal distance to allow myself from water to ceiling (keeping in mind that every inch counts)?

 

 

 

Decisions Decisions

 

 

Thanks for the help folks

[DuffyGeos]

I am in the same kind of predicament. I am using 250 MH because I have been told that since my tank dept is only 24" the 250's will be fine. If it was 30" or 36" then I should use the 400's. Make sure you plan out every inch of height with every thickness of material from the floor to the ceiling.

[DCReefer1964]

PAR meter tells it all !! 

[zygote2k]

PAR meter tells it all !! 

PAR meter only gives you numbers associated with crude light demands of some corals.

250w is plenty on a 125, just be sure that heat build-up doesn't become an issue with such a short ceiling. A fan may be required to vent the excess heat away from the tank and out of that room, otherwise you'll be heating the water.

[ridetheducati]

Do you plan to run a chiller?  If not, use 250w MH.  Strongly recommend using a switchable ballast 250w and 400w for flexibility.  Run 250w for a few months to gauge potential heat and humidity issues and switch to 400w if you want more growing power.  

[Tink]

Do you plan to run a chiller? If not, use 250w MH. Strongly recommend using a switchable ballast 250w and 400w for flexibility. Run 250w for a few months to gauge potential heat and humidity issues and switch to 400w if you want more growing power.

Exactly what I was thinking of doing. I've got Lumatek switchable ballasts.

 

Any thoughts on a reflector to use in this case? I'd like to be able to keep them closer to the water to free up some space if possible, but realize that LumenBright mini will push a good bit of light.

[Tink]

No chiller

[ridetheducati]

Does the 180g have center braces?  

[Tink]

Does the 180g have center braces?

Yes, it's a standard Marineland Reef Ready 180

[ridetheducati]

Use three 250w bulbs mounted 10-12" above water line.  

[Tink]

Is that taking into account the LB Minis? I ask because I've heard 16" as well.

 

Also, 12" to bulb or bottom of reflector?

 

 

Thanks for the feedback

[ridetheducati]

The LB mini performs better the more it is raised.  In your situation, we are only trying to light a 24" x 24" area.  How high can you mount the reflectors?

 

Measurements taken from bottom of fixture.

[ridetheducati]

Without getting nerdy about the topic, here is a good take away.  Reflectors like LB and Lumenmax are spot lights and need to be mounted higher to avoid hot spotting.  A reflector like Lumenarc3 can be mounted lower as its strength is spread. Each reflector has its strengths and weaknesses.  You need to determine the maximum height you can mount a reflector.  A LB mounted 18" is acceptable as well, granted you have the room.  A PAR meter will tell you how evenly the spread is at a given height.

[Tink]

Height to mount the reflector is an unknown at this point. If I mount them at 10" from water to the base of the reflector that gives me 11" of space between the top rim of my 125 sump and the 2x6 that is the left to right span supporting the 180 on my stand. So every inch higher decreases that access space, and every inch lower increases it. Obviously I'd like to have as much as possible without shooting myself in the foot lighting wise.

[Mike Mann]

Use three 250w bulbs mounted 10-12" above water line.  

I agree with that i did the same, and in your fish room to help you should put in a bathroom exhaust fan to help with heat, since no chiller

[Tink]

Without getting nerdy about the topic, here is a good take away. Reflectors like LB and Lumenmax are spot lights and need to be mounted higher to avoid hot spotting. A reflector like Lumenarc3 can be mounted lower as its strength is spread. Each reflector has its strengths and weaknesses. You need to determine the maximum height you can mount a reflector. A LB mounted 18" is acceptable as well, granted you have the room. A PAR meter will tell you how evenly the spread is at a given height.

Absolutely. I was looking at the Hamilton reflectors as an alternative if they would work better in my situation. I have no experience with anything other then LB Mini or Large though.

[Tink]

I agree with that i did the same, and in your fish room to help you should put in a bathroom exhaust fan to help with heat, since no chiller

I plan to install a couple centrifugal exhaust fans used commonly in horticulture, and connect them to temp and humidity monitors for environmental control.