This is my first post after four years on the sidelines benefitting from the wonderful advice and camaraderie of the TFP community. So here's a long overdue thanks for all of that!
Here's what prompted me to post today:
Our backyard swimming pool is looking like a crystal clear version of Lake Louise -- our formerly white plaster has become turquoise blue, creating an overall look that my wife rather likes, but I'm concerned about who or what may be being harmed by whatever chemistry is at work here.
Turquoise blue staining of the plaster surface, the skimmer basket, the DE grids... anything that's white and is submerged in our pool water for a sustained period (weeks) eventually turns blue. The plaster appears to be stained -- the blue doesn't come off with nylon brushing or even wire brushing. I occasionally find small turquoise rocks (<2mm in diameter) in the bottom of my filter.
Water is clear
Our pool chemistry has remained pretty stable at these levels since well before this condition set in.
Reading posts here on TFP led me to suspect copper in the water, and my local pool shop took a measurement today that confirmed its presence -- the guy seemed to be alarmed that it measured so high (3+ ppm).
1. Should I care? I'm told that it isn't really harmful to the equipment or the swimmers -- that this is basically just a cosmetic thing. Is that true? If so, and given that the aesthetics are (arguably) somewhat pleasing (Lake Louise effect), then is there any need to do anything?
2. If we do need to correct the situation, then what should we do? We live in drought-ridden California, so drain/refill is not a good option -- could make me public enemy #1 around here. And besides that, I'm reluctant to do anything until I know where the copper is coming from in the first place.
Root cause analysis:
Copper piping? I don't actually know if there's copper plumbing in our 60-year old pool system. The only plumbing I can see is either PVC or galvanized, but there is copper elsewhere in our home. However, nothing in the plumbing has changed in the timeframe that this problem has developed.
Acid interaction with SWG? My automated pH system feeds the muriatic acid directly upstream of the SWG. The guy at the pool shop theorized that there might be copper in the SWG (IC-40) and that it might be better to feed the acid downstream of the SWG. My understanding was that by placing the acid feed upstream of the SWG it would help reduce the calcium buildup on the SWG plates.
Thanks in advance for any insights y'all may have.
P.S. Happy Mother's Day to all the moms out there.