Lighting query

[flashyleopard]

I have asked about lighting before in an effort to understand and grasp a satisfactory lighting solution for my 125 gallon mixed reef. I will be having a handful of maxima and crocea clams, so I will ask here.

I am looking at the need to add a fourth 400 watt fixture to a 72''X18''X22'' tank. I think 3 400 watt fixtures, giving me 9.6 watts per gallon should be plenty for keeping corals and clams, even on the tank bottom, so a fourth would be overkill.I plan on using 10K bulbs or maybe a 10k and 2 lower kelvin bulbs, as I like a less blue loolk, but don't really want a yellow look either, just crisp, clear, true to the eye lighting appeals to me best.

I of course know that adding another fixture would be more light, but other than watts per gallon, how else does one easily obtain an accurate estimation they can apply to keeping corals and clams?Watts per gallon is not even all that useful, so I would like to hear your thoughts on 3 vs 4 400 watt fixtures.
Thanks in advance.

 

[johnnybravo234]

3 should be adequate. The watts per gallon thing isnt really useful.

 

[flashyleopard]

Your use of the word adequate makes me worry...lol.
Is it adequate as in, everything should do ok with three fixtures, but 4 would be adviseable or is it adequate as in, there's no reason that 3 fixtures won't result in thriving corals and clams?Using the 4th fixture would not be a costly endeavor, except for the cost it will add to the electric bill and the added risk to tank temps.I am not worried over the cost of the fixture, just don't want to get more lighting than is really needed to do the job and do it well.Thanks

 

[skinz78]

I have 2x400w mh with 14k bulbs in them on my 120g mixed reef. I persoally think this is too much light. I think watts per gallon is a mytyh, it all depends on your reflectors and bulb config. There is a heat issue plus alot of the lps don't do well in my tank. I blame this on too much light.

My tank measures 5'x20"x24"

I am currently tearing my 120g down and re setting up my 75g. I don't want to keep fighting the heat, plus the energy consumption is killing my pocketbook.

I don't think you would benefit from more than two 400w mh on your tank, but the addition of t5"s with atinic's would help out alot.

 

[flashyleopard]

Would you suggest just 2 400 watt fixtures then? I could do 3 or 4 250s also.I am not able to do a combo lighting option, b/c of cost and the location of the tank. It will be an open topped aquarium, so heat is less of an issue and I have lots of control over distance from the tank the lights go.I want a situation where I would never have not enough light, but not exclude too many species by having too much either.I value your opinion and experience.Thanks

 

[flashyleopard]

Still looking for your experienced opinions on this..thanks