How much light is required??????

[The Grizz]

I was hoping some one could tell me how much light is required for a tank with a depth of 18" . I am planning a canopy above the tank about 6 - 8 " so I can get into it easily. Need some idea of what to do. I think it is to shallow for 250 MH, could I go with all T5's and if so how many 54W T5's would I need.

If you have seen my 155 Bow Front build and coral pic then you have an idea of what I have for coral and lighting in there. The new tank is going to replace this one and I would like to use as much of the lighting that is in the 155 on the new tank ( 96" x 22" x 18") but I think the MH will be to much. Please let me know what you have on your tank if it is shallow or if you are a lighting guru tell me what I need.

Thanks to all in advance.

[24storm]

My frag tank is 12" deep 48" long and 24" front to back i have 2 250 watts over it will no problems i keep the lights about 12" to 14" off the water i have SPS and LPS in it.

Keith

[fencer]

8 t5 ho's would do it...well at least in a std 72 gallon....lights up every corner of the tank. I tried that last summer but went back to MH's/t5's

[Delphinus]

If it helps, I don't think there's such a thing as "too much light" but the caveat is that there is such a thing as "too much light too fast." If something is coming from a darker tank it could suffer light shock if not properly acclimated to the higher intensities, but usually things will adapt and be fine. I had 2x250W supp'd with 2x110W over my 18" tall 75g for 7 years before I shut that tank down last year, the halides were maybe 4" over the surface.

The nice thing about an 18" tank is that it's not terribly deep so it's a bit of good fortune in that you can pick pretty much any lights you want (t5, halides, etc.) and I think it would be hard to go wrong with any of them.

[The Grizz]

I would like to use the lighting I have in my 155 for this one as the MH Ballasts are brand new Ice Caps and the bulb's are same age as the ballast. The T5 I have in there are all 48" 54w so they will span the whole tank as they are overlapped in the 155 by 12" now. I just don't want to have a wipe out because I have to much light, if that is possible.

[the marine apprentice]

hey greg, id imagine if you just have them halides a bit higher then ya have them right now you will be fine untill everything gets acclimated to the light then if you wanted you could lower them a bit more. my 250 is sittin 16inchs above the water surface in my tank and my tank is 15inchs deep. and my clam is happy as can be

[The Grizz]

I was hoping to have the light's lower so that the canopy doesn't ahve to be so big. May be a shorter time sysle on the MH and a 4th set of T5 woul dbe a way to go.