Light LEVELS

[andre1000]

So what are the light levels for corals? whats considered low lighting and whats medium, high, etc in watts per gallon ratio

 

[mr_X]

there is no watts per gallon chart that works. you have to consider depth, spread, and the quality of light you are using. in other words, metal halide will penetrate the water a lot better than power compact fixtures will. a quality LED fixture can bleach most corals with very few watts used.

the only way to know for sure what your light is doing is with a PAR meter.
here are the suggested PAR numbers for different corals-

 

[iDream]

clams are in the medium light category? i though they were classified as high light? WTH

 

[mr_X]

250 PAR on the sand bed is pretty potent. i had a lot better color out of my LPS with much less. i would say 250 on the sand bed in a normal sized tank, like a 75 gallon maybe, would probably be something like 250 watt halides.