Reef Chemistry

[whatcaneyedo]

I'm sitting at 6 years the same as you but it sounds to me like all you need is to have some simple water changes done to bring your tank back to normal. If you add too much vinegar to counter act the rise in your pH you may very well cause a bacteria bloom as vinegar is often used like vodka or sugar for organic carbon dosing.

With my system I drop over 1 dkh of alkalinity a day if I take my Ca reactor off line. I've had it happen before where it went below 5 dkh and coral started dieing.

Test your water parameters and post them if you want a better answer. Its hard to advise based on speculation.