As I wrote in another post I had/have what I believe is black algae. The pool had been covered with a solar cover for a week or two and the first time I saw it most of the black dots were about 1/8" diameter or less. It was NOWHERE near as bad as it is in these photos: Black Algae - Trouble Free Pool
About the same time I was just schooled on CYA (I rent this house and had not heard of it before) and discovered it was about 200 ppm. Before I drained the pool I went in with a scuba tank and brushed all (most?) the black dots off with a 3M scrubbing pad.
Less than a week later I drained the pool but the property manager wanted to keep the deep end filled to keep weight in the pool. Once the shallow end was completely exposed I scrubbed the shallow end walls and floor with a diluted solution of bleach and threw in some algaecide for good measure (8.25% bleach was diluted about 5:1). I then hosed it all down to wash it into the deep end.
After the pool was filled I couldn't see any signs of the black dots from the deck but when I dove down with a mask/fins I could see some small black dots here and there (i.e. not tons of them) but they were even smaller than before (1/16" or less). I went back in with my scuba tank but this time most of the dots would not scrub off. It seemed as if they were embedded in small indentations in the plaster.
The pool has been filled for about a week now and they do not seem to be increasing in size. They are still not visible from the pool deck. I just got the water tested at a pool store (I know I know) and CYA was 24 ppm. Right now I only have a K-2004 kit. I've been trying to keep the FC above 5ppm at least until I get my K-2006 on Friday but I seem to be losing quite a bit of FC in the daytime (I'm in San Jose CA and we get LOTS of sun).
Questions:
1. Is it ok to use Trichlor tablets that I already have to raise the CYA or will that take so long that I should just buy some stabilizer?
2. If the 3M scrubber isn't removing the algae spots then I doubt a steel brush will but the article (at link above) said "brushing's importance in removing black algae cannot be overstated". The article said this was to "knock off the algae’s protective coating so that the chlorine can attack the algae itself". Do you agree?
3. Should I perform a SLAM once I get the K-1006?
Thanks for your input
About the same time I was just schooled on CYA (I rent this house and had not heard of it before) and discovered it was about 200 ppm. Before I drained the pool I went in with a scuba tank and brushed all (most?) the black dots off with a 3M scrubbing pad.
Less than a week later I drained the pool but the property manager wanted to keep the deep end filled to keep weight in the pool. Once the shallow end was completely exposed I scrubbed the shallow end walls and floor with a diluted solution of bleach and threw in some algaecide for good measure (8.25% bleach was diluted about 5:1). I then hosed it all down to wash it into the deep end.
After the pool was filled I couldn't see any signs of the black dots from the deck but when I dove down with a mask/fins I could see some small black dots here and there (i.e. not tons of them) but they were even smaller than before (1/16" or less). I went back in with my scuba tank but this time most of the dots would not scrub off. It seemed as if they were embedded in small indentations in the plaster.
The pool has been filled for about a week now and they do not seem to be increasing in size. They are still not visible from the pool deck. I just got the water tested at a pool store (I know I know) and CYA was 24 ppm. Right now I only have a K-2004 kit. I've been trying to keep the FC above 5ppm at least until I get my K-2006 on Friday but I seem to be losing quite a bit of FC in the daytime (I'm in San Jose CA and we get LOTS of sun).
Questions:
1. Is it ok to use Trichlor tablets that I already have to raise the CYA or will that take so long that I should just buy some stabilizer?
2. If the 3M scrubber isn't removing the algae spots then I doubt a steel brush will but the article (at link above) said "brushing's importance in removing black algae cannot be overstated". The article said this was to "knock off the algae’s protective coating so that the chlorine can attack the algae itself". Do you agree?
3. Should I perform a SLAM once I get the K-1006?
Thanks for your input
