Flucuating Ph Reading.

[greenie]

Recently had to shock chloinate but now when I test for chlorine it shows the bare minimum and when I test Ph, the test water initally turns yellow then proceeds to change to normal then to purple over a period of aprox one minute. I'm at a loss choosing which reading to go by. Anyone experienced this effect.

[dynamictiger]

When did you shock dose? It is not unusal for very high chlorine levels to bleach the reagents and give false readings.

[greenie]

The Shock Chlorination was just over a week ago now, it was pretty excessive! Your probably right, when the chlorine tablet hits the solution you can see the heavy purple released but it then clears up almost immediately.

[dynamictiger]

This is symptomatic of excessive chlorine levels. You can work out your chlorine level by diluting your pool water with distilled water at a known ratio and then testing the mixture.

With super chlorination you can bleach your pool shell if your levels are excessive, it is always a good idea to not shock past 15 mg/l or ppm.

HTH

[penny]

i am in charge of a community swimming pool, it is 43,000 gals. we use bromine. My alk, was high in the beginning, now i have it down to 100, calcium hardness is around 400, bromine,changes often, 4-6 range, but my ph, it may read 7.4 in am in the afternoon it may be down to 7.0 i add increaser, which does the trick but it doesnt stay long. anyone familar with bromine? thanks

[dynamictiger]

Bromine is acidic. It is probably decreasing the pH during the day as the demand increases. You could try compensating with an automatic pH controller dosing sodium bicarb.

HTH