Hello everyone,
I've got the mother of all problems with my pool and the experts are all telling me, "I've never seen this before".
Details: Inground pool, salt system, white plaster sides, only 3 years old, calcium at 900-1000 ppm. We use a roof mounted solar system to warm the water 5-8 hours per day and hardly ever use the heater.
I drained it just last year because of the same problem. The water here is hard to begin with and can be anywhere from 600-800 ppm out of the hose.
Two different pool service companies have tried to lower the calcium levels with chemicals balancing etc. They can't get it done.
The cell was cleaned just 2 months ago and now it's completely caked with calcium and needs to be cleaned again. The water is beautiful and crystal clear. But the surface is rough to the touch and hard on the feet. We've been using descalers to combat that, but now small brown marks are showing up on the plaster. They almost look like bird droppings and are hard to remove.
The interesting thing is that I believe this to be water temperature dependent as well because we have an attached spa with a spillover into the pool. The spa is naturally always warmer than the pool and the brown spots showed up there first and not in the pool. Now the spots are starting to show up on the most shallow areas of the pool, so it appears the warmer the area of the pool/spa, the more the brown calcium deposits.
My pool guy says some guy by the name of Dr. Laury (sp?) recommended tsp. I've done a search and understand this might raise algae levels, but that is not ever a concern with my pool as I mentioned earlier, it's super clear water.
I'm at wits end and don't know what to do other than try this tsp but need to know how much in a 23,000 gallon pool/spa?
TIA