Here are some pictures I took today, you can see the gray/blackish stains. What do you guys think they are?

http://i35.photobucket.com/albums/d1...Picture006.jpg
http://i35.photobucket.com/albums/d1...Picture003.jpg
http://i35.photobucket.com/albums/d1...Picture002.jpg
http://i35.photobucket.com/albums/d1...Picture001.jpg

Test readings today were,

Chlorine levels below 1ppm
pH 7.3
TA 210
CH 185
CYA over 100

I cannot get accurate readings on my CYA tests due to my test kit and high water temps here in Louisiana. Lamotte says that my CYA tests will be inaccurate with water temps over 85 degrees.

I am going to have to start using Cal-Hypo tabs from now on in this pool, I need to get that TA lowered and by adding Stabilized tabs it keeps making my pH levels decrease due to their low pH level.

I really need to drain the pool some and put in fresh water, the CYA level is way too high as well.