"Correct" levels causing issues

[jtech1]

I have had the pool for 9 years. Never had any major issues... all little things that I have learned from. Salt water pool, Diamond Brite finish. I have always kept the CYA on the low side and just run the generator more than probably necessary. Also, the calcium has usually been on the very low end of what SGM calls for. This year I decided to go for the recommended levels of both, and am seeing problems.

pH=7.4-7.6
TA=80
Salt=3600

First, I got my calcium up to 260 (SGM calls for 200-400). And within a week I started seeing little white specs appear in the pool. A few can be seen in the picture below. I can scrape them off with my finger. Are these deposits or leaching from the plaster? Should I get it back to 200 where it was before I saw any issues?

Second, I got my CYA up to 70 (usually stays around 50), so I can run my SWG less. With FC=5.5 and CC=0, I am seeing hints of algae around fixtures and in corners... also shown in pic below. I am well above the min of 3 for CYA=70, and in the recommended range of 5-10. So, why am I seeing algae?

Any advice on why I am seeing this when in the recommended ranges, and what I should do to solve it would be greatly appreciated!

Thanks!

 

[kul]

How often do you test?
Have you checked that your SWG is producing the correct amount of chlorine?

 

[jtech1]

It is early in the season right now, so I test frequently... every other day. FC has been at 5.5 +/- 0.5 for a couple weeks. Very steady. I have not had to add any chlorine to boost.

I have turned the SWG from 60% to 100% to get the level up closer to 10 and see if that helps... but, I'd feel better hearing advice of others to confirm this is the right move... and on what is up with the calcium.

 

[kul]

Seems this season many have learned they are using up more FC than they expected. Try running your FC on the high end so you have a buffer.

 

[proavia]

Welcome back!

What test kit are you using?
How old are the reagents?

We have this neat app called PoolMath
Download it and set up you pool info in it - then link it to your forum account (using same email and password as your forum account).
Enter all you test results in PoolMath and save them. This will allow us to see your test results. Alternately, post the results here in the following format for easy reading and review:

FC
CC
pH
TA
CH
CYA
Salt
Water Temperature

You referenced calcium in your post and said "SGM calls for ..." - What is SGM?

Use the FC/CYA Levels to determine the FC target range for you CYA level. Set the SWG to keep the FC near the top of the target range.

 

[jgofnj]

Seems this season many have learned they are using up more FC than they expected. Try running your FC on the high end so you have a buffer.

Funny - I noticed this too. For whatever reason, this season I been running my SWG a little higher (20%) then I had to the past 3 years this time of the year.

 

[jtech1]

Welcome back!

What test kit are you using?
How old are the reagents?

We have this neat app called PoolMath
Download it and set up you pool info in it - then link it to your forum account (using same email and password as your forum account).
Enter all you test results in PoolMath and save them. This will allow us to see your test results. Alternately, post the results here in the following format for easy reading and review:

FC
CC
pH
TA
CH
CYA
Salt
Water Temperature

You referenced calcium in your post and said "SGM calls for ..." - What is SGM?

Use the FC/CYA Levels to determine the FC target range for you CYA level. Set the SWG to keep the FC near the top of the target range.

SGM = manufacturer of Diamond Brite... I always used their numbers as a guideline for warranty purposes.

FC=5.5
CC=0
pH=7.4
TA=80
CH=260
CYA=70
Salt=3600
Water Temperature=80

 

[proavia]

CH of 260 should be fine. Many have CH higher than that.
No idea what the white specs are. Collect some and put a couple drops of vinegar on them - if it fizzes, it's calcium.

As for the algae... do an Overnight Chlorine Loss Test and report back.
Poor circulation or allowing the FC to get below minimum may be causing it.

Add your test kit to your signature
How old are the reagents?

 

[jtech1]

My CSI is slightly negative... so I would find it hard to believe this is scaling... is it possible that these small white spots are leaching? ie. calcium coming out of the plaster? If so, they were not there when the calcium was 180 when I opened the pool, but they are there now when the calcium level is 260. So, it must be some other parameter that induced this... the only other parameters of CSI are pH, TA and temperature. The pH is 7.4-7.5 so that is normal, and the TA is 80, which is also in the recommended range. So, could just rise in water temperature cause it? Should I let pH sit a little higher (7.6) and TA to 90 or 100 to raise CSI a bit? Or add more calcium?

Without knowing what the white bumps are, I could be making things worse by changing chemistry. Anyone have any idea what they could be with my levels? CSI on above levels is -0.54.

 

[jtech1]

CH of 260 should be fine. Many have CH higher than that.
No idea what the white specs are. Collect some and put a couple drops of vinegar on them - if it fizzes, it's calcium.

As for the algae... do an Overnight Chlorine Loss Test and report back.
Poor circulation or allowing the FC to get below minimum may be causing it.

Add your test kit to your signature
How old are the reagents?

Taylor. Just bought fresh reagents last year. I replace every 2 years.

 

[proavia]

Taylor. Just bought fresh reagents last year. I replace every 2 years.

Great that the reagents are still good.

What exact Taylor kit - they make a bunch of different models of test kits.
Add your test kit model to your signature ( K-2005, K-2006, K-2006C, etc).

https://www.troublefreepool.com/account/signature

As for the white stuff - don't do anything until you collect a bit and put a few drops of vinegar on it.

Do the Overnight Chlorine Loss Test
If you don't pass you need to begin the SLAM Process.