Dark Streaks in color plaster pool

[dawei213]

Hi all, I'm new to TFP but feel it will be my new home for the foreseeable future.

The pool in question is for a house we're buying. We're in agreement of sales but now are going back and forth with some inspection related material. In the end, it's the house my wife and I want to be in. In any case, for the pool, there are large dark streaks running from the steps from the shallow end of the pool and from the overflow of the hot tub area. There are also a good amount of discoloration throughout the plaster of the pool. I had a pool guy come out and he said the streaks looks like it originated from someone laying a garden hose from the shallow end and the hot tub area already filled and it overflowed from that area. I asked him is it just an aesthetic issue or worse and what can be done about it. He said it's mostly aesthetic and an acid wash should blend most of the streaks/discoloration but it'll be difficult to totally mask it. Of course he recommends a complete re-plaster.

Here's a picture of the pool:


So what do you guys think? Is it just an aesthetic issue? Can an acid wash lessen the difference in colors? Or would a full re-plastering be recommended?

btw, I have no idea about the chemistry makeup of the pool water but it's maintained by a pool company and not the owners.

 

[jblizzle]

Welcome to TFP!!!

Hard to see what you are talking about in the pictures. Most discoloration is just aesthetic and an acid wash "may" help, but that is also harsh on the plaster.

 

[dawei213]

Thanks jblizzle!

If you look towards the far end towards the steps, a very wide band of streaks that runs towards the deep end. Same from where the overflow of the hot tub into the pool. It's not a reflection onto the pool by a background object, it that's what might make it difficult to spot. The pool is about 11 years old. This is a house we'll be staying for a very very long time. I figure if it's just an aesthetic issue and an acide wash can't remove the streaks, I can live with it for another few years and then get it re-plastered as to "extend" the usefulness of the plaster. But an acid wash can at least make it less apparent, then it's an option.

I understand that acid washing essentially removes a thin layer of plaster. Is that what you mean by harsh on the plaster?

 

[Melt In The Sun]

Looks like copper stains to me...at least looking at the bench seat in the bottom right of the picture. 2 tests you can try: hold a chlorine tablet on the plaster and see if it lightens the spot, then hold a vitamin C tablet and see if it lightens it. Lightening by chlorine = organic, lightening by vitamin C = iron. If neither works, an acid wash will remove copper stains, but is hard on the plaster.

 

[jblizzle]

Wow, those streaks are crazy ... does kind of look like metal stains, but odd it would be so pronounced.

 

[dawei213]

Looks like copper stains to me...at least looking at the bench seat in the bottom right of the picture. 2 tests you can try: hold a chlorine tablet on the plaster and see if it lightens the spot, then hold a vitamin C tablet and see if it lightens it. Lightening by chlorine = organic, lightening by vitamin C = iron. If neither works, an acid wash will remove copper stains, but is hard on the plaster.

I don't settle until June 4th and move in until June 7th. Though I'm such a hands on type of guy I might just sneak in to get a water sample! The pool guy did mention it could be due to metal staining as well.

 

[jblizzle]

The pool at my current house was a swamp when we bought ... before closing I had already drained, pressure washed, and refilled the pool (before I became involved here). I also changed the lock on a shed and started moving stuff into it :lol:

 

[dawei213]

Haha, nice, I hope I can do the same. I will probably revisit this thread once I move in and am able to run some test.

Btw, great links in your sig. There's a lot of information but very good information. Thanks!

 

[gtemkin]

....... hold a chlorine tablet on the plaster and see if it lightens the spot.......

I thought I read somewhere in this forum that a chlorine tablet held against colored plaster can bleach the color dye from the plaster so I think you have to be very careful using this test on colored plaster. Probably shouldn't leave it in contact overnight however the pool appearance may be so bad in this case that discoloration from a test would be the least of the problems.

 

[dawei213]

....... hold a chlorine tablet on the plaster and see if it lightens the spot.......

I thought I read somewhere in this forum that a chlorine tablet held against colored plaster can bleach the color dye from the plaster so I think you have to be very careful using this test on colored plaster. Probably shouldn't leave it in contact overnight however the pool appearance may be so bad in this case that discoloration from a test would be the least of the problems.

Yeah, there's enough discoloration in the plaster that a test wouldn't concern me.