I have been doing battle with my pool. Its approximately 15k gallons, compupool saltwater generator. Mid summer i started getting these black dots in the pool. At first I thought it was nothing (this is my first pool) but then they started to multiply. I poured in the black algaecide (sun tropics brand) you get at the store and have been scrubbing with the wire pool brush but the spots are not going away. The spots after the algaecide treatment almost started to look like they were bleeding or rusty. Now I am starting to thinking I have organic matter or maybe fertilizer in there? I have a screened pool enclosure and an oak tree in the front of the house, the rest are palms or ficus in the back by the pool. The water is clean the chemistry safe for swimming but I have these horrible dots/spots everywhere.....What can I do, i need your guys expert help. I took a bunch of photos that I will try to attach.
updated 10/18/2013 with test results
I wanted a good baseline so i bought a taylor k-2006 kit. I performed all the tests but couldnt get the Calcium hardness test right, it was always purple, not blue and I felt like i was wasting regent.
In a 15-16k saltwater pool
TA: 80 ppm
CYA: < 30 super low could see the dot even with the whole vial filled so its less than 30
CH: inconclusive was always purple tried the test twice following the fading end point directions couldnt get it to work