My pool was extremely clear and well balanced until 5 days ago...
we had a problem with city water. We had no water for 2 whole days. During those 2 days we continued using the pool with no problem. (By the way the pool is inground plaster/tiles, 80000liters with an overflow canal and reservoir which receives extra water from the city with a floating switch, sand filter to which I add DE, SWG, pH regulator .I have a tft test kit and use it regularly and I have my SWG figured out so as to measure FC once every 2-3 days. Never had problems ever since I discovered this site) The water came back on day 3. The same afternoon the pool started to get a little cloudy. I immediately ran a fool test which was as follows:
CYA 70-75 (cant really tell where exactly the black dot disappears)
Borate aprox 40
temp 27 celcius.
I started running the pump 24/7 and boosted the SWG since I had 0 CC.
The following morning the pool was a light brown mess I could not see 3 inches down
the rest same as above
I backwashed the filter since pressure has risen 30% above normal and added DE as usual. Still ran 24/7.
The same afternoon the pool was worse than ever: extemely cloudy no visibility at all, color light brown
FC 10 TC 10 CC 0 (SWG at 4/10) pH 7.6
The overflow resevoir (which was half way empty during the no city water period) was even worse, very dirty. The city water is extremely dirty too. If you fill a glass from the tap you get a white cloudy thing and when it rans you can see the dirt in the bottom of the sink accumulating. (people in the village we live say the same and the mayor got sued allready).
I decided to flocc it and see what happens.... Does anybody have a better idea?