Hi I am a new pool owner, (the pool isn't new, but I'm new too it...) and this is my first post.
I have some round yellowish spots multiplying in the shallow end of my pool, in an area that gets continual sun during the day, where the vertical pool wall meets the bottom of the pool.
The pool walls are vinyl, brushing over the stuff with a nylon brush doesn't loosen up the spots or seem to affect them in any way.
I had my pool water tested by a pool company two days ago. Sorry but I don't have numbers, this is what I can remember, where I don't have the number I give a qualitative response....
Pool volume 110,000 Litres = 29,000 US Gallons
PH 8.0 (although my test strips continually tell me 7.4 to 7.6)
Alkalinity - OK
Stabilizer - none
Chlorine - low
Clarity - clear
Hardness - not sure
The pool company recommended a treatment of - liquid chlorine, 2Kg stabilizer, algicide, 50lbs Calcium chloride.
Since Monday I have
- put 2Kg of stabilizer in the pool (in a nylon sock, hung off of a ladder)
- 30L of liquid Chlorine (all on Monday at dusk)
- 1L Algicide (Monday night as well)
- 4 treatments of 7lbs of Calcium Chloride, pre-dissolved, spaced by 12 hours each
- Pool filter had been left on continuously.
As of Wednesday morning (today) my test strips tell me that Chlorine level is 'High', Alkalinity is good (120ppm), PH is 7.4-7.6
The water looks really good and I would think everything is great except for these yellowish brown spots that are multiplying. I don't think it is yellow algae because I can't brush the stuff off.
I will post a picture of the stuff soon, and get another water reading with actual number, but any help would be greatly appreciated!