Orange Water When TA/Ph Drop Very Low in Spring

[ruthelisabetha]

I have been on this site for 4 years and have learned so much from all of the experts here! Thanks to this site, we converted to the BBB method from pool store chemicals, although we do use an in-line chlorinator with 3" pucks for routine chlorination. We open, close, and shock with household bleach. We are having one, recurring problem - each year in the Spring (this is our 5th summer with our pool) our TA and pH drop very low and then the water turns a faint orange color. As soon as we add Baking Soda and 20-Mule Team Borax, the water almost instantly turns clear again. Does anyone have an idea why our TA and pH would drop so low each Spring and whether there is any way to prevent the drop? Thanks for your help.
Ruth in Rockville, MD

 

[chem geek]

Are there any chemicals used in the pool over the winter? If you had Trichlor pucks being used, then these are acidic and will lower pH and TA over time. The other possibility is that you have significant winter rain water dilution with rain that is low in TA and pH (i.e. acid rain). I don't have an explanation for the faint orange color.

I presume that your CYA starts low enough in the spring and that your season is short enough that using Trichlor doesn't have your CYA get too high by fall, correct? And that winter rain dilution or winter closing with its partial drain are enough to keep the CYA in check?

 

[ruthelisabetha]

Thanks for your response. Yes, we do have short season and our CYA always starts out low and doesn't really get high throughout the season. The past 2 years, we have experienced a lot of Spring rain, so perhaps we do have "acid rain". We live in the suburbs of Washington, DC, so perhaps the pollution causes it. Anyway, we have been successful raising the TA and the pH using baking soda and borax, so I hope we'll be OK for a while. Again, I certainly appreciate your insight.
Ruth in Rockville, MD