I think I found the real problem. You salinity is way to low at 0.025 you need to raise that to 1.025 slow and steady
What do you use to test ammonia? I only tewt ammonia during cycling since it shpupd never be there so used the cheap API kit and I've noticed their ammonia reading can be very hard to read, in all fairness I am colorblind though. Going with above we need to know what size tank. Also,is the tank 4 months old since set up or 4 months since the cycle completed? When did you add the fish and corals?