Can anyone identify what this depoist is (pic) ?

[dfattfp]

Hi,

So I have a bunch of this stuff (see attached pics) that has popped up in the deep end (big ones) and also spa seat and the wet deck (pics from). The brownish color matches the clay soil we have out here, i think that is where the color comes from. But nobody seem to know what it is. It's hard and crusty, I scrape it off with a putty knife (color remains) but comes back.

We have very hard water out here as well.

Had an acid wash (but guys that didn't know what they were doing), but came back.

Anyone know what it is and how to get rid of it?

TIA!!

 

[sktn77a]

Could be algae or rust (?). Get a chlorine puck and rub it on the spots. If they disappear, it's organic (algae, seed pods, etc). If they don't, get some vitamin C tablets and rub them on the spot. If it goes away, it's metal (probably iron). If nothing works, call in someone who knows what they are doing!

 

[ajw22]

Pool School - Metals in the Water and Metal Stains

 

[JamesW]

Maybe iron particles. Has any work been done recently that would produce iron particles?

Anything like metal grinding or metal cutting or steel wool etc will generate iron particles that can cause that type of staining.

 

[kadavis]

Search Calcium nodules on this site. I've seen spots like this from over zealous landscapers using iron oxide as a fertilizer. But they are easily removed and are not raised off the surface

 

[Realaxpooltech]

Fertilizer most likely.

 

[kadavis]

No you can see a faint hairline crack if you follow the nodules. On balance wrote a great article about this with pictures of what is happening

 

[dfattfp]

thanks.

how much work to just plaster the pool again? Do they take all the old off?

 

[JamesW]

They can chip out the old plaster and redo it or just cut around the tile and fittings and go over the old plaster.

Either way, it's a big job. Not one to be taken lightly.

 

[sktn77a]

Replastering can cost anywhere from $5000 on up, depending on the finish used, the size/complexity of the pool and whether they chip out the old plaster or just acid wash/bond-coat and re-plaster. Trouble is, if you don't know what it is, it may just come right back.