What kind of stains? - with pictures

[jefeyessica]

We are kind of new to the whole pool thing, and I have a question about some staining on my plaster pool. We refilled our pool a few weeks ago, and I did notice some staining before we drained it, but the water was always so dirty and green that it was hard to tell what really was going on.

Now that I have done a lot of reading on this forum, and my water is clear, I started worrying more about the stains. I took some pictures of it, does anyone know what kind of stains these are? The stains are all over the place (about 85% of the plaster surface), and are kind of a reddish/brownish color. There are also a few really light spots.. is that the original color, or are those somehow bleached lighter?

BTW the pictures were taken at dusk

Current test readings:
FC 4.0
Ph 7.2
TA 150
Ch 310
CYA 25

Thanks for your help.

 

[JasonLion]

If this first appeared right after cleaning up algae, then it is probably organic staining, which will fade over time.

You might as well check to see if it is an iron stain. Hold a Vitamin C tablet against a stained spot for 30 seconds. If the stain vanishes in that spot or lightens significantly then you have iron stains.

 

[jefeyessica]

So I've been inspecting the "stains" some more while swimming. It almost looks more like damage to the plaster. The surface of the stains have a different texture - more rough. If it is damage, how do you repair something like that? They're not algae stains. I don't have any vitamin C, so haven't been able to try that out yet.

 

[JasonLion]

If your PH has been very low, you might have pitting of the plaster surface. If so, there isn't any way to fix it short of a complete re-plaster job.