I don't understand that. To my knowledge, CYA has no appreciable affect on TA and a fairly minimal affect on pH (but a little)Yes and no. PoolMath does not indicate it does in the effects section but CYA adds buffering in an uneven way, it is pH dependant.
Yes it does, very roughly at a pH of 7.5 one third (1/3) of your 20ppm CYA addition will increase your TA by ~6ppm and is detected and/or included as part of the standard TA test. The increase will be a little less as the pH increases and a little more as it decreases. Reducing TA using the acid aeration method will only decrease the carbonate alkalinity portion of total alkalinity. It will not reduce CYA or borate if present.Does adding CYA affect TA levels?
I know it drops PH, after all it's an acid! (-0.4PH for +20CYA)