Excessive sand in filter, 1+ years after refinish?

[Newdude]

I also don't have a way to weigh small amounts to do the experiment on my sand (my breaking-bad years are well in my past )

Digital kitchen scales are cheap with many under $15 at the 'Zon. You might need it for carb counting one day.

 

[JamesW]

does my action plan change based on that determination (marbelite vs. quartz?) or is that just to figure out if the builder put in the wrong material?

Just trying to get a better assessment of exactly what plaster you have.

I also don't have a way to weigh small amounts to do the experiment on my sand

Put some in acid and see if all of it dissolves or just some of it dissolves.

The exact amounts are not critical; we just want an approximate percentage that dissolves.

Do not use a capped jar for the test because the reaction produces carbon dioxide gas, which will cause pressure buildup if sealed.

Watch the TA and CH to see if they increase at the same rate, which would point to the cement dissolving.

Try to keep the CSI as close to 0.0 as possible to reduce plaster loss.

Try to keep the pH as high as possible without going over about 8.0.

Try to keep the TA as low as possible while maintaining the CSI at 0.0.

 

[sktn77a]

Anthony-Sylvan, and I'm pretty sure they were just a GC subbing the work to various local crews.

Subs are irrelevant, the GC is the person responsible - they chose the various subs. The calcium in your filter has to be coming from somewhere. Possibly your fill water but much more likely, your plaster (whatever it is). Get the builder back before it all dissolves away!!!

 

[JamesW]

Note that the video is not entirely fair in comparing quartz aggregate vs. white marble aggregate plaster.

This is because the cement is what reacts with acid and causes the aggregate to fall out.

So, it does not matter how reactive the aggregate is if the cement is dissolving.

They both use the same cement, so the plaster can have similar life.

The aggregate does make some difference, but not as much as people think.

If the sand bubbles with acid, then it is probably calcium carbonate.

Quartz does not react with acid.

Put some of the sand in acid to see if some dissolves and some does not.

Clean, dry and weigh the sample before putting it in acid and then clean, dry and weigh any remaining sand that does not dissolve to see what percentage is calcium carbonate vs. quartz.

For example, if only half of the sand dissolves, then the aggregate is probably a 50/50 mix of quartz and marble.

Stop by the builder and ask for a cup of marbelite aggregate and a cup of quartz aggregate to compare to what you have.

Try acid on some of each sample and see what reaction each has with acid.