Lighting Height

[littlejohn17]

I am setting up a 125G tank (72Lx18Wx21H), using 3 400W MH with 20,000K bulbs. The reflectors are similar to the Spider brand. We are not exactly sure what we are going to keep in it yet. My question is: How high should I mount the lights above the water surface for the different livestock (LPS, SPS, clams, etc.)? Thanks for the help.

 

[jeep9783]

Depends on the ballasts and bulbs really then when can give you a little bit more info

 

[jade76]

wow....I personally think 3-400watts might be a little overkill. I would route for 250's (My 90 is 24" high and 250's do great.) Anyways...As far as the height of the bulb, Opinions may vary but I think somewhere in the range of 10-15"

 

[jeep9783]

Well with 20k i don't beleave it is overkill

 

[jade76]

its something called heat...

 

[derek_s]

Jade is right, if you use a quality 20k lamp it will probably be much more than you really need. But if you do use the 400s, you can probably mount the lamps pretty darn high off the water, like Jade said, but I'd even venture 10-20"

Be ready to invest in a chiller fo-sho.

 

[jaustin]

If you mount them a bit higher than normal you should have no problem dealing with the heat with a fan or two, like one pusher on one side and one puller on the other. 3 20K halides will be real nice. What brand bulb and ballast did you get?

 

[jeep9783]

jade76;202935 wrote: its something called heat...

Its called a fan...a chiller...Running lights at night...etc...

Really I think I know what heat is I have 8-400w halides and 2-250w...Heat is somthing that is easy to rid its self of...I am talking about the quality of 20k he uses if he buys garbage then he needs to be close quality he can start high and slowly lower

 

[littlejohn17]

I bought this retro kit -

 

[jeep9783]

Nice I would say mount them about 12-15 inches off the water as since you have 400w you want to use all of that power just make sure that you keep the softies on the bottow and the sps up high...you also will have to start the sps on the lower side of the tank not the very bottom but a little high off the sand and i move mine up about 2-3inches a week till they are king of the mountian then things start to get crazy with the growth...if you have canopy you can get some nice flush mounted fans that will move a great deal of air saving some time on bulb life and the temp of the tank...all and all with those 20k you are going to have great coral color

Chris