He tested his Refractometer with RO water. This works but the calibration fluid is better. You are missing something! Do you have any reefer friends? take a water sample to someone else and run every test they have. I have to ask you this only because I went through the same thing. Your water sorce. Do you know if your water sorce has chlorimines in it? Do you have the new style carbon block in your RO? Check with your water company and see if they are putting cloramines in the water. This happend to me and I did not know they changed from chlorine to chlorine chloramines and ammo. the normal carbon in your RO wont remove all the chloramines. I lost many SPS. I found the easy way to fix it is by just adding some chlorine, chlorramines and ammo remover to my RO water. Problem solved. I also added it right to my tank and the die off stoped.
