joyfulnoise

I have a fiberglass inground pool, 7m x 3.5m (23ft x 11.5ft), 25000 liters (6600 US gallons). On starting up for the summer the pH was very low, so I over a few days I added a few kilos (several pounds) of Soda Ash (sodium carbonate) to raise the pH to the correct range. A few days later, purple...

I started to get a few TFP Experts off topic from another post I started and it is a long-time issue which I would like to get some opinions. Matt (JoyfulNoise) made some good comments in my other thread and it isn't that I don't trust him but I'm just looking for some additional info so I...