Been lurking on TFP quite a while and have learned a lot...thanks to all who contribute to such a great forum!
Did first fill on our dinky 10' Vinyl AG about a week ago, been adding and testing as per pool school but I have a couple of questions about reducing TA to keep the PH rise in check.
My first problem is getting an accurate measure, because TA and PH seem to be off the top end scale of my tests (TA 180 and Ph 8.4 respectively) However my water company rather helpfully provide some very detailed info about my water on their website - mine is TH 303 and CH 120. So I used these numbers in poolmath (BTW I know TH is not strictly the same as TA but at this level it's close enough!) and have been adding the doses of MA. For now, I'm also using Dichlor as a sanitiser to build CYA, I guess the Dichlor should be PH negative too?
After adding MA, the Ph does seem to drop a bit to about 7.6 - 7.8 but when I test again a couple of hours later, it's back at/above 8.4
Question is, should I just try increasing the MA dose until I get down to Ph 7.2? how quickly should I add more MA? At the moment it seems that the Ph is creeping back up in the space of a couple of hours! I'm guessing that with my high TA, the risk of overshoot is quite low (at least for the time being) but I'm new to all this......!
Thanks in advance!
Edit to add:
CYA: 10, based on 6% CYA per 10% FC Diclor added but I don't have a test to check!
Water is crystal and the pool is clean