Need Help, Patches of Rust? Calcium?

[Ugmul]

Hi all, I've been managing my pool since June using BBB, and I have not had any problems.

This morning when i went out to do my daily levels check I noticed a couple markings on the pool that looks like rust. They are small in size, about the size of a dime. They don't brush off, and its smooth to the touch. I have maintained levels and everything has been good.

This Mornings Readings:

FC 6
PH 8.0 (lowering this back to 7.5 as we speak)
TA 140
CH 240
CYA 50

CSI(using pool calculator) is .38

PH rose a little high yesterday from rain I think, but its back down now.

If I plug in numbers for my PH being high CSI it rose up alittle above the .6, but it was short.

Is this Calcium scaling? Is the best ways to remove is just a pumis stone?

Thanks

 

[duraleigh]

Calcium scale is generally grey but it can be other colors. It's normally rough to the touch, too.

Get a tri-chlor puck and place it on the spot for 2-3 minutes.....see if that removes it. Report back.

 

[Richard320]

It could be rust, very easily. Worst case is the rebar in the shell is rusting and leaching through. Far more likely is that some tiny piece of steel ended up in the pool. A nail head even. I had one that apparently broke off and took a fly when the fence was torn down and it left a huge blotch, which lifted with Vitamin C tablets. Another common source is fertilizer and plant foods. One granule of ferrous sulfate can leave a good mark. Got roses? Fertlize them lately?

 

[Ugmul]

Well I got the stains up with a pumice stone without much effort. There were 2 patches of these spots, one on a seat in a neat small triangle. Other was 3-4 spots in the deep end that were random. I am thinking your right that it was some type of organic or metal that fell in. I noticed the spots on the steps first and figured it was from someone sitting in it with metal on their pants/jeans or something. We had party last week and one or two individuals didnt have suits with them.

The other spots were underneath a tree that overhangs our pool. Anything could have fallen and sunk down.

But the fact that the stone took it off within seconds, and that it was still smooth leads me to believe you were right about a piece of metal got in and moved a bit before being sucked up in the vacuum or brush.