Brown "gravel-like" spots.


New member
Feb 5, 2020
Perth Australia
I'm brand new here and was following a thread similar to this, and now that I've registered I've lost it haha. Anyway our pool has about a dozen spots I can best describe as an amoeba-like appearance....the centre is almost like a little piece of brown gravel that is attached to the pool liner; it's hard to scrub off even with a stiff brush. I have picked it off with my nail but it leaves a gravely-type residue. Surrounding the brown spot is a light brown/black stain. I have a regular pool maintenance person and he added an extra dose of chlorine but that didn't seem to make any difference. He suggested waiting until winter ( I'm in Australia, it's mid summer now). But that's a few months away and I'm concerned this is causing small holes in the liner. Thanks for any suggestions.


TFP Expert
LifeTime Supporter
Jan 4, 2016
Sydney, NSW, Australia
Welcome to TFP! Good to have you here :)

First step is to read up on Trouble Free Pool Care in Pool School. Personally, I also like this article for a condensed version: TFPC for Beginners

Test kits are available from Clear Choice Labs: Kits – Clear Choice Labs
The price might seem like a lot, but you'll save it back by avoiding pool stores and pool maintenance persons.

As an example, an "extra dose of chlorine" if in any solid or powdered form, is adding other things to your pool which may simply be making matters worse.

I would try brushing the spots with a nylon pool brush, just three or four firm swipes across them, you don't have to get crazy on it, then checking back in an hour or two to see if they lightened. If they do lighten, it's just organic stains, and with repeated brushing the chlorine will take care of them.

I makes little sense to wait until winter to fix a pool staining problem. That may just fit their schedule better.