Minor setback recently. Not 100% sure of the cause, if it is due to my water change pump heads not being perfectly in sync, or if I screwed up mixing up NSW once before I ran them for a while. But my salinity had fallen to 1.020. Noticed a small branch of my light purple acro had died, but needed to travel for work so didn't have time to really look into it when I noticed it. Came back to it completely RTN'd and dead. Zoas seem to have melted back a bit as well. Interestingly, those seem to be the only ones having suffered so far. Added some saltwater to the top off, plus mixed up the new saltwater batch at 1.03 to bring it back up to target. I'll be watching salinity going forward like a hawk now. Hopefully just a one time setback, I have enjoyed using this pump for water changes and up until recently the tank has done well thanks to it.