Hello Everyone,
I have a 16' x 32' rectangular Intex pool (about 14K gallons), vinyl liner, sand filtration. We purchased this last summer and maintained clear water throughout the peak season using a regimen of 27% strength peroxide oxidizer, biguanide sanitizer, and extra algaecide on a limited basis. The pool was initially filled with city water trucked in, but then topped off here and there with water from our well which is quite hard. The pool sat uncovered and untreated for about 4 months during Texas' colder months, w/ pump circulating about 8hrs a day, accept during freezing temps. During this time we noticed stain buildup on the walls and outer perimeter of pool. Figuring it was just algae, I shocked the pool with peroxide waited a day, then added startup doses of algaecide waited another day with the pump recirculating. Then I did a couple initial vacuums removing loose debris and leaves. During these initial vacuums, I noticed that while debris was being sucked up, the scrubbing action during vacuuming was not successful getting back to completely clean vinyl and in many locations there was almost impenetrable thin crust or scale. I did a couple more rounds of algaecide, waiting 24 to 48hrs followed by vacuuming and scrubbing. I am at a point now where no progress is being made and the perimeter stains are still present. I can remove stains with my finger nail or something very abrasive, but they do not respond to the bristles on brush cleaning attachments, and since this vinyl I am not sure I want to go more abrasive than this.
Thinking this might be metal staining due to our hard water, I tried the vitamin-C tablet test using about 10 tabs in one spot and I see very little response over an hour time (maybe slightly lighter). I used 10 localized tablets just in case the higher level of peroxide was cancelling out the ascorbic acid; (Not sure if that is a thing). I left a chlorine puck on the stain for 3 to 5 minutes and no response; no lightening of the area, no nothing. I sprinkled some ALUM in a small area just because I had some on hand. After it dissolved there was little indication of it doing anything, but when I ran a bristle brush over the area, a little bit of the scale came off, but nothing ground breaking. I tried rubbing an orange on some areas with no success. I do not have any noticeable calcium deposits anywhere, but thats not to say it could not have settled on the floor in the winter months. Anyways, before spending money on stain removers, I wanted to see if anyone had some thought on how to remedy or identify this. Is this metal staining, calcium buildup, algae that needs continued treatment and weeks to properly break down, or just scrubbing with something extra abrasive that is still safe for vinyl?
Attached is a pic of the algae scale/crust that I was able to get off during the vacuum process, but most of it does not budge. You can see little nubs where it conformed/embedded to all the little indentations in the vinyl liner.
Regards
Current water properties:
alkalinity: 120
ph: 7.0 to 7.2
peroxide: 60 ppm
biguanide: 0 to 5 ppm (have not treated with this yet)
I have a 16' x 32' rectangular Intex pool (about 14K gallons), vinyl liner, sand filtration. We purchased this last summer and maintained clear water throughout the peak season using a regimen of 27% strength peroxide oxidizer, biguanide sanitizer, and extra algaecide on a limited basis. The pool was initially filled with city water trucked in, but then topped off here and there with water from our well which is quite hard. The pool sat uncovered and untreated for about 4 months during Texas' colder months, w/ pump circulating about 8hrs a day, accept during freezing temps. During this time we noticed stain buildup on the walls and outer perimeter of pool. Figuring it was just algae, I shocked the pool with peroxide waited a day, then added startup doses of algaecide waited another day with the pump recirculating. Then I did a couple initial vacuums removing loose debris and leaves. During these initial vacuums, I noticed that while debris was being sucked up, the scrubbing action during vacuuming was not successful getting back to completely clean vinyl and in many locations there was almost impenetrable thin crust or scale. I did a couple more rounds of algaecide, waiting 24 to 48hrs followed by vacuuming and scrubbing. I am at a point now where no progress is being made and the perimeter stains are still present. I can remove stains with my finger nail or something very abrasive, but they do not respond to the bristles on brush cleaning attachments, and since this vinyl I am not sure I want to go more abrasive than this.
Thinking this might be metal staining due to our hard water, I tried the vitamin-C tablet test using about 10 tabs in one spot and I see very little response over an hour time (maybe slightly lighter). I used 10 localized tablets just in case the higher level of peroxide was cancelling out the ascorbic acid; (Not sure if that is a thing). I left a chlorine puck on the stain for 3 to 5 minutes and no response; no lightening of the area, no nothing. I sprinkled some ALUM in a small area just because I had some on hand. After it dissolved there was little indication of it doing anything, but when I ran a bristle brush over the area, a little bit of the scale came off, but nothing ground breaking. I tried rubbing an orange on some areas with no success. I do not have any noticeable calcium deposits anywhere, but thats not to say it could not have settled on the floor in the winter months. Anyways, before spending money on stain removers, I wanted to see if anyone had some thought on how to remedy or identify this. Is this metal staining, calcium buildup, algae that needs continued treatment and weeks to properly break down, or just scrubbing with something extra abrasive that is still safe for vinyl?
Attached is a pic of the algae scale/crust that I was able to get off during the vacuum process, but most of it does not budge. You can see little nubs where it conformed/embedded to all the little indentations in the vinyl liner.
Regards
Current water properties:
alkalinity: 120
ph: 7.0 to 7.2
peroxide: 60 ppm
biguanide: 0 to 5 ppm (have not treated with this yet)
Well, you seem to have quite the pool cocktail going on there. Baqua pools are a bit tricky with some owners who continue to use them, while others are happy to convert to chlorine as we prescribe here at TFP. Typically, organic stains would show some change with the chlorine tab/puck. Iron should react the Vitamin C almost immediately, especially if applied directly to the stain. If the stain, grew darker from any of these methods, it could be copper which would be possible from all the algaecides added if they were copper-based. On top of all that, you have hard chunks that can be removed from the liner. Then there's the baqua itself. Let me ask you the following:
