help!! fish dying...my coraline has turned white

[Maui4Me]

I moved a friends 3 year healthy system to a different used tank at my place. We replaced the silicone seal as it was previously fresh water, I will test tomorrow for nitrite. How can I get my ammonia down ? I've been treating ick with temp increase 79 to 82 and a reef safe natural product herbtana but I was to turn off protein skimmer