I was thinking of using some diluted bleach in a spray bottle and a little elbow grease to treat this. Should I be concerned if I use the garden hose to rinse it, with remnants going into the pool? 
Is this black lichen on my sandstone rock?
- Thread starter Brayne
- Start date
- Jul 21, 2013
- 55,121
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If you are at or above your target FC level, that will handle whatever flows into your pool.
