Brown smudges on wall/floor of pool

[amnporter]

Hi all. I'm new to this site but found it to be very useful. I'm having issues with brown smudges on the wall/floor of my pool. I've tried shocking the pool, brushing with brush, brushing with chlorine tab, and also vitamin C tablet to no avail. All my levels are in perfect range and were checked 2 days ago at Pinch a Penny. I've attached pics of what i see. Any help will be appreciated.

I have a 10k gallon in-ground gunite pool. Not sure of pump size. Levels are normal.

Thanks,
Chris

 

[Bama Rambler]

Welcome to TFP.

Telling us the levels are perfect does us no good. We need the actual numbers. And how you got them.

Try holding a tablet on a couple of the stains for a few minutes and see what happens.

 

[amnporter]

I'm sorry I don't have the printout of my levels handy right now. I take my water to the local pool store to get my levels checked every week and if they tell me I'm in the normal range, I discard their printout. I was letting a chlorine tablet lay on the spots for about a couple hours. When I removed it, the spot as well as the chlorine tablet turned purple. What the heck is going on in my pool?

 

[Bama Rambler]

That sounds like copper staining. It can be almost impossible to remove. You might want to invest in a Jacks stain identification kit.

Do you use any products that have copper in them (algaecide, 3-in-1 or 4-in-1 chlorine, mineral system, etc.)?

 

[amnporter]

Since my last post, I've tried spot out from pinch a penny which worked for the most part. That, in combination with leaving a chlorine tablet on some of the darker bigger spots, cleared most of these smudges. But they are coming back again. Could these be caused by oak trees? Scrubbing does remove them. Again, pinch a penny continues to tell me my levels are perfect. What to do?

 

[Bama Rambler]

Spot out is just granular Trichlor. If it worked, your stains are most likely organic. Though you may have some metals and organics mixed. I still would like a full set of test results.
I also suggest you get the stain identification kit.

 

[amnporter]

My levels are as follows:
Total chlorine - 5.0 ppm
Free chlorine - 5.0 ppm
pH - 7.6
Total alkalinity - 125 ppm
Calcium hardness - 400 ppm
Stabilizer - 100 ppm
Total dissolved solids - 1200 ppm

My chlorine is a little high because I just shocked it a couple days ago. My alkalinity hasn't been out of range, but I have some muratic acid to get that back to normal range. I'm really starting to think that these stains my be from pollen left on the birdcage. Any thoughts?

 

[Bama Rambler]

Do some reading through pool school and you'll soon learn that your chlorine isn't high. It isn't even high enough for a CYA of 100.
You'll also learn that you haven't even come close to shocking your pool. Your CH is on the high side an tds doesn't matter.

If the trichlor lightened them they certainly could be pollen.