What does it mean when your tap water varies wildly from one day to the next?

[adapted]

I just filled a storage barrel that's reading 8.35 straight out if the tap. Yesterday it was 7.1.5. The tank is about 6.8 (it is just cycling, without any fish)

I'm sure it's the city water authority trying to overcome some mistake they made or some anomaly caused by inadequate processing facilities or inadequate employees.


In any case I can see this playing hell with water changes. I'll be curious to see what the values are in 24 hours, but as much as I'd rather not I think I'm looking at having to add something like Discus Buffer or Neutral Regulator to overcome whatever it is that's causing these wide variations at the tap.

[Elliots]

If the pH difference between my tank and my change water is .6 or more I change only 20% but I change more frequently than the 3X weekly I usually change 50%. I always check both pH before a change. There is something called "Winter Water" that is very different from normal water. Perhaps something is happening to your water due to cold temps in MS. this year?

[adapted]

Well the good news is that the pH dropped back to 7.15 overnight -- temp is now 83 -- so whatever the fine folks at the water administration added has mostly dissipated. The tank is holding at 6.6 (I added a teaspo0n of Discus Buffer to experiment with getting a stable pH there... I hate adding the stuff but I think it may be the best choice for pH-crash-prone water.

Does anyone know what city water services typically add to temporarily raise pH?

[OC Discus]

That ph drop I believe is what is called "gassing off". Some tap water sources will have a ph drop within about 24 hours of being aerated and heated. If this is happening with your water, my understanding is it is better to age the water, heating and aearating it, before adding it to the tank. Let the ph stabilize in the aging barrel rather than buffering the tank.