Ok, now I'm starting to think they (spots) were brought on by the size / frequency of WC's. I have started doing more / smaller ones, & spots seem to be fading.
I was doing big ones - close to 50%. Now, closer to 20%. I add water straight from tap (plus prime).
I'm not smart enough to understand why you need to age water, & I don't have enough room to do that anyway. I think I could get away with bigger WC's if I did.
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