Recent content by Ora

Hi mate, some quick update here: Try to use Vitamin C tablet to rub the black spot today. Some small black spot can be easily removed. Some large and old black spot require extra elbow grease, but in the end, it is been removed as well. Guess I can conclude it is a metal stain for sure. Heavy...

Thank you so much mate!! I will grab some dry acid and Vc tomorrow and give a shot. Will update photo in this thread ;)

BTW, I tried use tri-clor tablet on top of the blackspot overnight which does 0 effect. That makes me think it is not black algae. And it stains my surface a bit :cry::cry::cry:

Thank you so much. Is above method might damage the fiberglass surface? I am in panic mod atm as one of the pic shows a bit yellowish stain on surface. It is due to using tri-chlo tablet on top of the blackspot, as I originally think it is black algae:cry: which cause a bleach stain.

Hi Texas, Thanks for the suggestion. I have attach photo of the copper based algaecide I used perviously. I pour half litre of it to the pool When the blackspot start appears, there is 0 copper in pool. The recent increase of copper in water test happens after I pour the algaecide. Is there...

Hi guys Newbie here and recently moved into a new house with a Fiberglass pool. It was built in 2014. Mineral pool with chlorinators. Pump running 8 hrs/day. As we recently moved in and found the poor seems a bit greenish and cloudy due to the recent heavy rain. After we thoroughly cleaned the...