changing MH lamps

[popnglow]

will changing from 20k to 14k too quick hurt my corals?

 

[Nanook]

There is probably a significant increase in PAR, so I would either raise the lamps and slowly bring them down, or use a couple sheets of metal screening material to help dim the light. Take a screen off after a week and the second one after another week.

 

[Michigan Mike]

What bulbs? Is the bulb old?
Raising the light a few inches or running the bulb for less amount of time and slowly adding an hour every couple days until its back to normal.

 

[jda]

it depends on what you are coming from vs. what you are going to. Not all 20K are low putters when compared to all 14K.