Calcium buildup on grout under waterfall

[PatricksPool]

Friend has a new in ground pool and I’ve been helping onboard him into the TFP ways. We’re wondering what the best course of action is for calcium buildup within the grout for the moss rock under the waterfall. Pictures attached.

Latest test results:
32k gal microfusion
PH 7.6
FC 7
CC 0
TA 60
CH 175
CYA 50

 

[mknauss]

To remove it, the best thing is to use diluted muriatic acid and a brush. Wear PPE.

To prevent it, will be difficult. But not letting it get as bad as it is will help.

The chemistry results indicate a very low CSI for a plaster pool. I would suggest getting the CH to 350 ppm and watching the TA.

 

[PatricksPool]

To remove it, the best thing is to use diluted muriatic acid and a brush. Wear PPE.

To prevent it, will be difficult. But not letting it get as bad as it is will help.

The chemistry results indicate a very low CSI for a plaster pool. I would suggest getting the CH to 350 ppm and watching the TA.

Thank you sir...we were following the Microfusion recommended values for the most part for CH: 150 – 250 PPM. But I can definitely see the issue on the lower end.
I think our next step will be raising the CH towards 350. We’ll try the MA/brush on the existing stains.

 

[mknauss]

Sounds good. Do be careful as the acid will splatter. Also, natural rock is really problematic. Hopefully they can just run the waterfall when they really want to. Also, be sure to see if there any hiding places of algae at the top of the water fall.

 

[Pepperdinegal]

Sorry to jump in on your thread, but what ratio of MA to water would you recommend for something like this? Also, is it safe/okay to put that mixture in a water bottle and spray on the heavy calcium? I have the same issue with the grout between the porcelain tiles under my waterfall.

 

[mknauss]

but what ratio of MA to water would you recommend for something like this?

Try 4 or 5 parts water to 1 part acid. Again, be careful.
Spray bottles typically have metal springs in them and will not last long. You can try it.

For grout lines, I suggest using a pumice stone to get the bulk of the scale off first. The acid will eat the grout as easily as the scale.
To really clean grout, use kieserite blasting.