Is there any reason not to use this?

[Richard320]

I still have some weird staining/blotchiness in the pool which Vitamin C didn't touch. I suspect it's scaling, as the pH was really high when I first started testing it after I moved in. In an older thread someone suggested trying to sand it off.

Well, the big stain is still under about 4' of very cold water and I don't own a wetsuit. But the weird stuff on the steps of the spa is reachable. Especially when the heater is on and I'm in it! Just because I've got the beginner's obsessiveness going on, I brought a scrub brush and a scotchbrite pad in with me this evening. Pretty much every inch of the spa got a good scrubbing with the brush, and the steps and the corners got a scrubbing with the pad. They do feel much smoother.

Is there any reason I shouldn't use these?

 

[JasonLion]

Those are fine on plaster that is more than a year old, though you might have better luck with a pumice stone.

 

[PoolGuyNJ]

Wet/Dry 220 grit sand paper works well and gives a good feel of control too if it's calcium. A picture of the stain(s) helps.

Scott

 

[mas985]

I've used wet/dry sand paper before it is seems to work really well and easy to control how much of the surface is removed.

 

[geekgranny]

Above suggestions are good if they work. Pumice stones are great and come in different grit "sizes". The scale on my steps was so hard, when I acid washed last year, I had to use an angle grinder with a concrete disc. I only got one done before I slipped going down to deep end and tore a rotator cuff tendon but I spent about two hours on one step and was on my second concrete disc when I stopped. My plaster is blue so the contrast between the blue and white scale made it easy to see when I got down to the plaster.

BTW... the scaling stained more easily than the plaster and held the stain more tightly.

gg=alice

 

[Leslieslsa]

Also have your spa checked for metals. (depending on the color of the stain) But sometimes heaters can emit some copper, and that will cause staining. Then you could just add some Spa metal free, or something similiar, and that should remove the stain.

 

[Richard320]

Wet/Dry 220 grit sand paper works well and gives a good feel of control too if it's calcium. A picture of the stain(s) helps.

Scott

Here ya go, from the older thread. The spotty one is the step, and the light circles have grown some since scouring. The edges of the steps are totally white now. I think it may be calcium that got stained. The pH was very high when I moved in.
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