Neglected pool. Is this scale?

[tjf]

This pool was neglected while the house was unoccupied (foreclosure) and an investor brought it back to clear to sell the place. The pH was at 8 when I tested it. Is this calcium scale, or is the finish just messed up? The stained areas are definitely rougher than the unstained, but honestly, when you rub anywhere, the finish sorta flakes off in your fingers (like a course beach sand). There was a noticeable pile of this grit down by the main drain.

Thoughts? :?

 

[linen]

If the stains are "rougher" than the surrounding material, then it sure looks like scaling.

Post a full set of test results. See: http://www.troublefreepool.com/pool-school/read_before_you_post

 

[tjf]

Sorry --

FC 7
CC 0
CH 210
pH 8.0
TA 100
CYA 80

 

[linen]

Your csi value is not extremely high (+0.41 assuming 90F water temp...higher than +0.6 is considered at risk for scaling) but that does not mean it wasn't high in the past. For now, you keep your ph at the low end of 7.2 and that will drop your csi down even further from 0.6. For details, see: http://www.troublefreepool.com/pool-school/calcium_scaling

If the discolored surface is not much rougher than the rest of the pool surface, you could try placing a vitamin C tablet on a spot and see if the stain disappears. If it does, then the stains are likely caused by some other metal in the water such as iron.

 

[onBalance]

I think Linen has it right. It looks like scale and then iron, that has deposited onto the surface making it rough and discolored.