Recently changed over from a gravel and wood set up to sand, wood and plants. Looks much better but the discus are now hiding. I kinda guessed this would happen really, but is it normal, or are they just adjusting to the new setup?
how long has it been since the changeover?
are water stats all ok?
My guess is that they just need time to adjust, try leaving the light off for a day and see if they start to venture out more,
once they are comfortable in their new surroundings they will start to relax and act more like what your are used to seeing