Scale?

[Michaelg90]

I noticed these last few days there is small white sand like deposit around the corners of the pool in a few places. After reading ABC of pool school twice it sounds like it could be scale. However my logs (which can be viewed on my profile) using the app show I haven’t let me PH go above 8 ever. I try to maintain around 7.5 or so and with Alk around 50/60 I find it helps keep it there. I checked my CH thinking it could be calcium leeching from the plaster but that’s 250 and within range and haven’t dipped below ever. I read up on CSI and I have kept it below .60 always and usually in the .40 to .30 range. Here in FL with the water hotter it has helped in these months.

I attached a picture. Is this normal for small pebbletec pools? what can or should I do to correct? Maybe I’m just being OCD but trying to be the best pool owner I can be and protect my investment.

Thank you for your continued assistance on the site.

 

[jmikeb]

to me( no expert here) it looks like your csi has been quite negative most of the time.
my question is why is your fc so low?

 

[Michaelg90]

Well I keep it at 4.5 or so and each day about 1/2 ppm is used so in the logs you will see where I added FC.

 

[Michaelg90]

Correction to original post CSI -.30/-.40 not positive.

 

[mknauss]

Does the material 'poof' when you brush it?

 

[Michaelg90]

Not really.

 

[Michaelg90]

I read a bunch of posts on here last night about scale and CSI and I’m having trouble understanding how this can happen. It seems to me based on going back and reviewing my entire 6 month history of the pool that I should have etching problems not scale. My CSI has been below -6 the whole time and never went up past 0, PH has always stayed below 8. Alk is around 50-60 normally as that’s where the PH seems to stabilize. Just confused on how this can happen if it’s scale. Any thoughts? What should I be doing today given my most recent test:

P/H 7.5
Alk: 50
FC: 6
CC:0
CYA:40
CH: 225
Temp: 88

Just completely at a loss as to how this can happen. Added extra photos below

 

[mknauss]

Does not appear to be scale to me. More likely is the normal mottling of dark plaster pools.

 

[Michaelg90]

So this is normal? I understand when they blend this it’s by hand and in a wheel barrel lol but it seems to me it might be more spread out and not in random places. Tried to capture a few more this morning in the shade

 

[mknauss]

Have a look through some of these.

 

[Michaelg90]

Have a look through some of these.

So I looked through and the more I look at the photos the more I’m convinced it’s not mottling. Those marks seems to be almost like someone dipped a brush and swirled the plaster unevenly. The photos I took show white sand paper like deposits which by definition make it seem like scale but I’m baffled as to how that could have formed with the water maintenance where it’s at. I would need high PH and excess calcium to form and CSI to be positive above +3.

 

[mknauss]

Drive your CSI to -0.6 for awhile and see if they disappear.

 

[Michaelg90]

Well based on my last reading that’s making the PH at 7.3. I would imagine this will lower my ALK a little further. Should I raise it to 70 and then drop PH to 7.2? How long would I keep at these levels? 10-14 days?

I know you and I have had discussions about bleach. The moment I joined this site I switched from tabs to bleach. I currently use it today. You mentioned in the past that although PH rises with the introduction to bleach, it is lowered back down to the current level once bleach is used. So if I don’t add acid and bleach is added, if the PH is then raised to 8, until use wouldn’t the water be sitting at this higher CSI?

I test the pool Monday, weds and Friday. I will had bleach on each of those days and acid if necessary. I usually bring the FC level to 5-7 which will stay above the minimum until I show up for the next test. My concern is in that time from Monday to weds or from W to Friday if the PH gets higher causing scale? When I perform the next test nothing indicates it’s been out of range so I was just curious if anything could occur in the inbetween time until the FC is used.

 

[mknauss]

The effect of adding bleach is not an issue.

As long as your TA is above 50 and pH stable no reason to raise your TA.

I assume you are brushing the pool regularly.

 

[Michaelg90]

The effect of adding bleach is not an issue.

As long as your TA is above 50 and pH stable no reason to raise your TA.

I assume you are brushing the pool regularly.

Yeah I brush twice a week. And vacuum weekly and wash filter every two weeks.

 

[Michaelg90]

How long should I do this for? In the event they don’t go away after ____ timeframe what would be your recommenced next step?

I read that a no-drain acid wash would be an extreme step so should I contact the PB if I can’t remove it? In the event they recommend that option is there something I should counter?

 

[mknauss]

Take a look after 30 days.

If this a new plaster job, contact the PB. I doubt they will do anything, however.

You clean your filter every two weeks??? Bummer. I clean mine once a year. Are you waiting for your filter pressure to rise by 25% over clean pressure?

 

[Michaelg90]

Take a look after 30 days.

If this a new plaster job, contact the PB. I doubt they will do anything, however.

You clean your filter every two weeks??? Bummer. I clean mine once a year. Are you waiting for your filter pressure to rise by 25% over clean pressure?

No I have just followed the instructions on the new pool docs from the PB as it states to clean every 2 weeks for first year.

I’ll try it for 30 days. So I’m going to lower PH to where CSI goes to -.6. Should I be brushing every other day or something during this process? I have a metal wire brush I use for tough spots but doesn’t always work?

Once a month is up, I take it I should have this above -.3 from there on out?

 

[Michaelg90]

Does a product like jacks magic scale pink stuff help moving forward or should I avoid buying this product?

 

[mknauss]

Long term it is best to keep the CSI above -0.3.

No idea on the additive. I have never used any potions.