Concrete inground plastered pool.
[FONT=open_sansregular]
TF-100 TFTestkit [/FONT]
Pool was re plastered in April this year (i.e. 4 months ago). A couple of weeks ago I started noticing strange black stains:
View attachment 54182
View attachment 54183
View attachment 54184
View attachment 54185
Looks like it is getting worse.
I doubt this is algae, since stains do not come of from brushing (even with a metal brush).
I have not tried to rub it with a vitamin C (btw, where can I get pool vitamin C tablets, and how exactly to try that?) to understand whether it is caused by the iron / copper binding to the plaster. The water is clear, it is municipal, and the plaster looked ok for 4 months.
I am not certain whether a 4 months plaster could start exhibiting some bad chemistry. It was supposed to be a regular diamond dust plaster, I would expect to see this problem earlier if the plaster itself was bad (but let me know what you guys think).
Thank you
[FONT=open_sansregular]
TF-100 TFTestkit [/FONT]
FC | 10 ppm |
CC | .5 ppm |
TC | 10.5 ppm |
CYA | 35 ppm |
CH | 675 ppm |
TA | 140 ppm |
PH | 7.7 ppm |
Pool was re plastered in April this year (i.e. 4 months ago). A couple of weeks ago I started noticing strange black stains:
View attachment 54182
View attachment 54183
View attachment 54184
View attachment 54185
Looks like it is getting worse.
I doubt this is algae, since stains do not come of from brushing (even with a metal brush).
I have not tried to rub it with a vitamin C (btw, where can I get pool vitamin C tablets, and how exactly to try that?) to understand whether it is caused by the iron / copper binding to the plaster. The water is clear, it is municipal, and the plaster looked ok for 4 months.
I am not certain whether a 4 months plaster could start exhibiting some bad chemistry. It was supposed to be a regular diamond dust plaster, I would expect to see this problem earlier if the plaster itself was bad (but let me know what you guys think).
Thank you