I've been taking care of my pool for a couple of years now, but have been battling calcium deposits the entire time. For a brief history:
When I purchased the home (Summer 2012), I noticed that there was white calcium scale on the flagstone at water level. There was also brown stain on the plaster under the water.
I left it alone until last year (Spring 2014), when I used the Jack's magic test kit to determine that the brown stains were also calcium. I used Jack's magic #2 (Copper and Scale stuff) to remove the brown stains. Of course, this involved installing a bypass on my pool heater, and dropping the PH to something close to 6.0 for quite a long time before it all went away. Towards the end of the treatment, I noticed that I was starting to get hard brown deposits on the pool floor (which didn't have anything to start). All the brown stains from the wall were removed, but by the end of the treatment, I had a few hard brown deposits on the floor that wouldn't come off.
I called the Jack's hotline, and they told me that what probably happened is that I had small cracks in the plaster surface, but they were being filled in by the calcium scale. By the time I removed the scale, it opened up the cracks, and calcium leaked out from the plaster.
So, I have a question: Has anyone experienced this, and how did they handle it? The brown deposits have grown over the winter, and now I have quite a few. I'm not sure what was worse: The original brown stains or the new brown clumps on the pool floor. Of course, I could use another round of Jacks Magic products, but I'm worried I'll just make it worse.
For background, I believe my pool is about 7 years old (I've owned it for 3 years). I do my best to keep the chemistry in check, but the PH rises very quickly, so it can often get up to 7.8 or 8.0 before I have time to add acid and reduce. Also, I drained and filled last year after my calcium level got above 500 (after completing my Jacks magic treatment)
Pool Type: 25,000 gallons, plaster, with SWG and DE Filter
FC - 4.0
pH - 7.2
TA - 90
CH - 250
CYA - 60
Thanks in advance for your help, and sorry for the long post.