Metal halide replacement

[JMAN15]

What's a good way to acclimate a tank when replacing the metal halide bulbs?

 

[kfowler]

People use either screen or light difuser (eggcrate). If possible, you can raise the lights and then bring them closer to a normal level. I personally just swap them out.

 

[aninjaatemyshoe]

I still don't get the reasoning for this... the light that hits corals in the wild is so variable with cloudy days, differing water surface conditions, and changes in the turbidity of the water. One day could be one heck of alot brighter than the next in the wild, so why can't we do this on our aquariums?