Stick with it bro. We've all been through these frustrating times and we feel your pain. Just remember nothing good happens fast. This may take a little time. Keep the tank stable and things will sort themselves out. If you are concerned about metals then you might want to consider a triton test. The test is a bit pricey but it will tell you if you have any elements out of whack. I was having a funk go through my tank a while back, sent off a triton test and discovered I had elevated levels of tin. Do you have any used equipment that could be rusting inside? A few months back I thought my water was kind of yellowish so I ran some BRS rox carbon and man did my corals object. I have a 155 and I put a mesh bag of about 2 cups of BRS rox carbon in the sump and my water improved but I think it stripped other things out that the corals rely upon. I must have used too much. After I removed it things got better.