Acid Wash to improve look of plaster?

[6XSBChamps]

Moved from here.
I'm curious about the acid wash process. I have midnight blue plaster that has faded, a lot. When I have to add MA I do it over the tanning ledge and it brings the blue color back but I only pour a little in one area and i quickly swash the water around. I've seen people talk about acid washes where 10 gals of MA get dumped in to bring the color back on the plaster. I know MA shortens the life of the plaster and we're basically removing a layer of it but is it as simple as adding a heavy dose of MA as needed? I assume there are pump/filter concerns?

 

[Nectarologist]

Moved from here.
I'm curious about the acid wash process. I have midnight blue plaster that has faded, a lot. When I have to add MA I do it over the tanning ledge and it brings the blue color back but I only pour a little in one area and i quickly swash the water around. I've seen people talk about acid washes where 10 gals of MA get dumped in to bring the color back on the plaster. I know MA shortens the life of the plaster and we're basically removing a layer of it but is it as simple as adding a heavy dose of MA as needed? I assume there are pump/filter concerns?

Hi. I don't know about the MA in a filled pool but figured I'd chime in since there have been no replies. When I worked for a pool company we would drain the pool and scrub the walls and floor with a deck brush after we poured the acid (mixed with some water) on the area. Looking back on it we were an OSHA case waiting to happen but luckily never got inured.

 

[JoyfulNoise]

Read this post by @onBalance -

Thread 'The Zero Alkalinity Acid Treatment'
The Zero Alkalinity Acid Treatment

 

[JoyfulNoise]

A better process instead of acid washing would be to drain the pool and mechanically polish the plaster surface. But that is hugely labor-intensive and would cost a lot. Pool service companies do acid washes because they are quick and cheap and give immediate results even if they do a lot of long term damage to the plaster surface.

 

[onBalance]

Note that when acid removes a layer of plaster, it does so in an etched manner, meaning that the surface becomes more rough every time an acid treatment is performed.