limewater self-purification and tapwater

Thanks for the terrific article on limewater! I was interested in the self-purification of limewater with heavy metals and phosphorus. This raised the question for me of whether other undesirable things in tapwater, such as pesticide traces, would also be precipitated? Inother words, to what extent can we do without RO water when using limewater?

The self purification article should post in a few days (May 15) at Advanced Aquarist. I hope you like it!

As to pesticides, I don't know. Some may precipitate, some may degrade at high pH, and others will be just fine.:(