I second that dosing is the problem. Test your alkalinity. If I were a gambling man, I'd bet it's pretty high. Kurt's assessment is absolutely correct. Dosing an excess will cause your pH to increase. Just curious, why are you dosing? It doesn't seem like you have the kind of livestock that would require any kind of dosing. I'd discontinue the dosing for a while--not necessary IMO
To my knowledge, most salt mixes already contain the trace elements and other things that coral need. What kind of salt are you using?
Pure Water is relatively around 7.0. Thincat just had a brainfart. For someone that contributes as much as he does--it's no big deal.