Will My Leather Survive?

[Sparkfarmer]

I am using RO/DI water. I'll be checking my params again tonight, but they have been steady with Alk = 8 - 10 dkh, CA @ 380 - 420 PPM, S.G. = 1.024 -1.025 and PH around 8.3. Might have slipped though in the last few days. Just did a 20% WC. I missed one last week, but have been pretty consistant keeping up.

I also have in my tank a GBTA, Hammer and frogspawn LPS, some Xenia, Kenya tree, mushrooms and Rics. Everyone else is doing well. The leather was clear of all other corals...The damage to the Leather was mostly on the side with the Aptasia, and thats why I think its the culprit.