Black algae in 23 year old white plaster

lawalters

New member
Sep 14, 2020
3
Charlotte, North Carolina
It's time to replaster our 23 year old pool. In the past 5 years, black algae has been a problem. Have gotten several quotes to re-plaster. I really want the same solid white plaster that has been used for years but I have been told that the plaster today is not the same formula and that the black algae will come back thru. I have been told that if I plaster, it will only last a couple of years. My old plaster lasted over 20 years and has only started looking bad recently. I really don't like the pebble finishes due to the roughness and the fleck appearance. Any suggestions?
 

Desert Dog

Well-known member
Apr 4, 2020
284
Alpine, Ca
I don't know about old plaster vs. today's plaster, but...... are they not chipping out the old? I would want a total chip out down to the shell. You can run into problems with just plastering over the "old" plaster. If your old plaster is removed, I would suspect all the algae would go with it. If your water is balanced properly, the plaster can last 20 years. I'm sure someone will be along soon who can go into detail on a total chip out vs. just plastering over old.
 

lawalters

New member
Sep 14, 2020
3
Charlotte, North Carolina
I don't know about old plaster vs. today's plaster, but...... are they not chipping out the old? I would want a total chip out down to the shell. You can run into problems with just plastering over the "old" plaster. If your old plaster is removed, I would suspect all the algae would go with it. If your water is balanced properly, the plaster can last 20 years. I'm sure someone will be along soon who can go into detail on a total chip out vs. just plastering over old.
Thanks for the reply. They will be chipping out some of the plaster. Anywhere that is pitted, chipped, or holding algae. I hope somebody out there knows about plaster formulations and if it's true that they don't make it like they used to. My suspicion is that the pebble surface is about twice the price as plaster so they may be trying to "up sell"
 

Desert Dog

Well-known member
Apr 4, 2020
284
Alpine, Ca
I would ask for a quote on removing all the plaster not some. You don't want the new plaster failing because of the 20 year old plaster underneath it.
 

YippeeSkippy

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Jan 17, 2012
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Evans, Georgia
 

ajw22

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Jul 21, 2013
21,141
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
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