will CH lower over time if none is being added?

[keithpgdrb]

My CH is a bit on the high side for a vinyl pool. In my research here, its not at a danger level, but I would like it lower. I used to use the bags of shock weekly, not realizing that I was adding Calcium each time.

I no longer use that stuff. SO, will my CH gradually go down from pool use? splash out, etc. last I checked, my fill water is not very hard. when I need to top off, I dont think it would effect my CH much.

is rain water better?

 

[mknauss]

Rain water has 0 CH.
If water loss is from evaporation, the CH will not go down. But if from splash out, over flow, etc, the CH will come down over time.

 

[Newdude]

Drain some before big rains and it will help. If you have a permeable cover, the off season rain will REALLY help.

 

[EmilyOTR]

hyjacking this a bit, it can go down but overall can it stay the same season after season particularly on pools that close in the winter?

 

[mknauss]

hyjacking this a bit, it can go down but overall can it stay the same season after season particularly on pools that close in the winter?

If your fill water CH is essentially the same as your pool water CH, and you have very little evaporation (or rain refills the pool as necessary all swim season) it can stay pretty much the same.

 

[EmilyOTR]

If your fill water CH is essentially the same as your pool water CH, and you have very little evaporation (or rain refills the pool as necessary all swim season) it can stay pretty much the same.

ah so you are saying it would potentially go up, not down because of the fill water?

 

[mknauss]

Yes, if you are using fill water for all purposes, including evaporation losses.
For instance, my pool, no, and I mean no, rain all summer. I evaporate about 50 gallons per day in a 6000 gallon pool. Fill water CH is 250 ppm (I actually use softened water now, but this is for information). In four months I would add a full pools volume due to evaporation, and my CH would increase by 250 ppm.

 

[EmilyOTR]

ok so it makes some sense that mine stays very stable over the past 6 seasons? since I get a good amount of rain but it's mostly refilled by fill water? And we don't lose 50 gallons a day! We have the opposite weather from you!