lights off for maracyn?

[DeCoY]

Today i noticed my black molly had white puffy around his eye and it seems to be popped out a lil. I just started maracyn and the guy at the store told me to leave the lights off for 5 days (planted tank) and to remove the carbon from my filter. the box says continue normal filtration. just wondering if i have to leave the lights off.

thnx

 

[pl*co]

It helps reduce the stress on the fish, but not so good for plants. Can you take 'em out for a few days and put them in a bucket by a window or do you have too many?