Gunite Pool Surface Help - Bloody Feet

bigdave

LifeTime Supporter
Jun 14, 2007
62
Boise Idaho
We recently moved into a house with a 13 year old gunite pool. The bottom surface was dirty so we paid a company to drain and acid wash the gunite surface. The pool is now clean, however the surface in the shallow end of pool is rough. When the kids play basketball for a few hours they come out of the pool with bloody feet all scrapped up and rubbed raw.

The gunite surface overall still looks healthy, however this rough surface is a problem. What options do I have to help fix this issue? Drain and Sand? Resurface? Please provide any experience to help our family.
 

bigdave

LifeTime Supporter
Jun 14, 2007
62
Boise Idaho
Has anyone attempted to sand the surface of Gunite to solve this rough surface? Any experience with how to do such a task?
 

Geebot

Well-known member
Aug 19, 2013
851
Has anyone attempted to sand the surface of Gunite to solve this rough surface? Any experience with how to do such a task?
First of all, the surface should be plaster, which is applied to a gunite shell. I'm assuming you're referring to the plaster being rough (and if someone came out to clean it they likely would have warned you if the plaster had fully eroded to expose gunite (which would be pretty rough)). Rough plaster to the point of making your feet bleed is pretty unusual. Is it a specialized finish with an aggregate? Is it a uniform color or does it have small speckles of aquarium-gravel bits?
 

JamesW

TFP Expert
Mar 2, 2011
15,023
Gunite is the structural concrete shell of the pool. It's about 9" thick.

Plaster is the waterproof layer on top of the gunite. It's about 3/8" thick.

Acid washing removes the cement and exposes the aggregate in the plaster.

The main types of plaster are white marcite with calcium carbonate aggregate, quartz with quartz aggregate and pebble with pebble aggregate.

Acid washing can make the surface very rough and abrasive.

Acid washed marcite or quartz can result in a sandpaper type surface.

Acid washed pebble can result in an exposed aggregate type surface.

The plaster can be polished.

What type of plaster do you have?
 
  • Like
Reactions: bigdave

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
10,612
Evans, Georgia
I'd suggest some water shoes. You can get some inexpensive ones online. Will help them play those pool games far more comfortably and surefooted.


Maddie :flower:
 
  • Like
Reactions: bigdave

skimmerswimmer

Well-known member
Jul 30, 2013
299
Long Island, NY
I've seen pebble get polished on Youtube before, but I don't know if this is something that would work with your pool:


Have you checked that the surface problem is not calcium scale? This can usually be addressed with acid wash/bath and brushing.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
6,839
Northern NJ
Aggreate surfaces are polished using diamond pads.

If you can get a pic through the water I'd like to see what your pool finsih looks like.
 
  • Like
Reactions: bigdave

bigdave

LifeTime Supporter
Jun 14, 2007
62
Boise Idaho
Appreciate all the feedback. I will work on figuring out the surface and getting some pictures posted. My gopro broke so I need to borrow an underwater camera to get this done.
 

JamesW

TFP Expert
Mar 2, 2011
15,023
Looks like standard white plaster with calcium carbonate aggregate.

The acid wash exposes the aggregate and makes the surface rough.

It can be sanded if you can find someone local who knows how to do it.
 
  • Like
Reactions: bigdave

sktn77a

Gold Supporter
May 16, 2010
1,153
Chapel Hill, NC
When our pool was first built, the marcite surface was very rough and was causing our kids toes to bleed! Builder was totally worthless and just said "it's normal"! Well, over the years it appeared to get worn down but it would still wear out a Polaris 380 body every 2 years. We had the pool resurfaced a couple of years ago and the plaster was MUCH smoother. Still usinng the same Polaris body and looks like it has at least a couple of years left in it.
 
  • Like
Reactions: bigdave