Hi, i have a limestone fountain and i'm having a hard to preventing algae growth. Fountain was built about 4 months ago. First time i had algae i used Kem-Tek Algaecide and it killed the algae within 24 hours. Ive been adding about 2 ounces per week and it is no longer effective. My gardener drains the fountain once a month but algae keeps growing every two weeks.
I've contacted limestone tile manufacturers and pool guys and none seem to be familiar with limestone. They all recommended i don't use chlorine long term to keep algae from growing. Should i be concerned about using chlorine or bromine to shock kill the algae? Should i be concerned using it long term on limestone?
Any help on how to kill the algae and upkeep my fountain long term would be greatly appreciated!