if you hHow much baking soda did you add in total?
+1000Soda ash (baking soda cooked) is the alkalinity additive in most 2 part dosing schemes. You just added a huge amount of alkalinity additive to your tank....hence the rise in alkalinity. The effect of adding alkalinity on your pH is very short lived. If you keep adding it the pH will keep going down and you end up where you are.....very high alkalinity and eventually the same pH.
Don't chase pH or use additives to get it to a certain number. Make sure you have adequate air exchange and don't fret it.
a better choice is to test cal and alk then look at kalwasser (cheap) it adds both cal&alk. underdosing saturated kalkwasser in the ato will help.



