acros dying

didnt seem to be a big difference between brands, bulbs are cureent 250 watt 14000k acros are all in different locations throughout tank different heights.

 

based off of what youve told me and if nothing else has happened my best guess would be changing salts played a part, the age of your bulbs are a hard call without a par meter, but if they arent putting out what they should be then changing the salts would have a greater affect.

acros dont like change, so when you changed salts there could have been a spike.

here are somethings that can and will cause rtn and bleaching:
sudden temp change
heavy metal corrosion in your water column.
sudden change in salinity
sudden change in pH

there are more but ill get a hand cramp typing, heres a site for ya
SclerDisF8

 

this really sucks this morning 2 more acros w/rtn but others close by show no sign of anything . might be time to look at a FOWLR.hard to believe that switching salt could do this but who knows tryed to frag what i could off the newest victims have to see what happens.