Selective rtn

[Doug]

Another weird thing about rtn, is its selectivity. Im still working on my new sump and don't have my Osmolator running as I wrecked it. So Im dripping a walk mix into the sump.
Yesterday I noticed I have some corals receding. Absolute panic of course, hoping its not an all out event happening.
Seems to have stopped. {fingers crossed}. Only reading off, is the salinity dropped from 1.026 to 1.013 because of my stupidity. Not sure thats the reason of just coincidence.
Anywho, its the corals that receded thats weird. One over here, one over there. Not the one next to it. I have two large milli frags on the same rock, inches apart. {same coral}. One receded completely and the other is fine. A couple of my new CC frags also.
Like closing your eyes and throwing darts to pick things.

[Doug]

Lost my beautiful deepwater. Seems to have stopped however. No idea besides my original theory, what the cause is.

[Myka]

Ugh. The salinity drop would do that - that's a huge drop. That would also cause a huge alkalinity drop (as well as other parameters). Depends how quickly it got that low, how long it was that low, and how quickly you raised it back up.

[Doug]

It dropped over 2 nights I think. Never bumped all up after incedent. Let salinity raise itself very slowly. Still in process. Appears to have stopped. {knock on wood}.