Tank crashing

[asylumdown]

You should get a test kit that can isolate carbonate alkalinity from borate alkalinity. I went through a mini SPS crash that I simply could not explain a couple of months ago because my total alkalinity kept testing in 'normal' ranges.

For a variety of reasons my borate alkalinty was actually making up too much of that percentage and my carbonate concentration was dangerously low. As soon as I realized it and I corrected the carbonate alkalinity specifically (even though it made the total alk higher than I normally like), the 'crash' completely stopped and has now reversed.

I only mention it because you said that part of your calcium reactor was clogged for a while. If you use a salt with a lot of borate it can really start to obscure a problem with low carbonate over time.