Slow upward trend for Phosphate and TDS

[CMH-CVG]

Since opening in May, the chlorine pool has remained clear and mostly a TFP thanks to the advice from this group, use of Taylor K-2006C and poolmath.
The chemical requirements have been mostly +2gal Liquid Chlorine about every week, with pH/Alkalinity/Hardness moving in and out of range when it rains, or having to add 500gallons of city water to counter evaporation (have a flow meter attached to hose), so I am letting them fluctuate instead of actively treating it with chemicals to reach a target level. I also add 3 tricolor tablets to the floater about every 2 weeks.

I often get the water tested at Leslies pool to have a read on Copper (0.5), Phosphates (116) and TDC (1400) (7/18/2023 values), however I follow the Taylor K-2006 and pool math app for any action.

Why this post? While the pool remains clear, I have noticed a slow increase in Phosphates and TDS and seeking advice if there is any indicated action to take.

Additional observations:
a) Prior owners did a poor job painting the gunite pool white, as the paint keeps flacking off every time the Dolphin Explorer E70 robot cleaner is used
b) Overnight test shows no Chlorine loss
c) The submerged walls, while no visible off-color, feel slick to touch, so I have began to brush the sides and floor with a pole/brush. Occasionally I noticed white clouds being formed when brushing the floor, suggesting some sort of floor deposit. (LIKELY THE SOURCE OF INCREASED TDS)
d) Backwashing every 2-3 weeks does not show much visible cloudiness
e) New variable speed pump running 2,900rpm 24/7 (have not tested variable speeds yet)

 

[Donldson]

TDS is the total dissolved solids. You're constantly adding stuff to the water, so of course it's going to continuously go up. And the stuff you see puffing up on your floor isn't dissolved, so it's not the source of dissolved solids. Chlorine, acid, baking soda, calcium, stuff like that is contributing to the TDS.

This is why we preach education and self-reliance over listening to the pool store. Their testing will have you fretting over completely normal things. Your phosphates are very low, but I'll bet they didn't tell you that. Time to give up the bad habit of pool store testing if you want to take full control of your water.

 

[YippeeSkippy]

-Some city water suppliers actually *add* phosphates to the water because it helps coat the inside of old pipes.
-Your TDS is everything in the pool to include salt, calcium, chlorine, skin cells, yada yada yada. Not a worry.
-Why is your Free Chlorine so low?? You're inviting algae to a party if you keep it so...... or you may well already have it since you mention slick floors Remember that pucks *add* CYA which means your FC requirements go up also. Keep your FC high enough to allow for the sun's daily burn off yet leaving you with enough coverage.
-You should be following the FC/CYA Chart-
-Only backwash when your filter pressure rises 25% over the clean pressure.



Maddie

 

[Newdude]

TDS is a junk stat. It is mostly Calcium and Salt and has a wiiiiiiiiide range of possibilities. There's no telling one person that theirs is no good.

A TDS of 1900 (all calcium) would be an issue.

A TDS of 3000 (all salt) would be low for a salt pool and entirely fine for a liquid chlorine pool.

Disregard TDS, and anyone who pushes it.

While it's true that phosphates are algae food, it's a moot point if you sanitize properly so algae can't grow. If you don't sanitize properly, the unsightly algae you'll get is harmless. The bacteria, viruses and pathogens that'll also flourish are the worry, and they don't feed from the phosphates so again they're no concern.

 

[YippeeSkippy]

To rule out algae please run an Overnight Chlorine Loss Test-->.
Overnight Chlorine Loss Test

 

[CMH-CVG]

TDS is the total dissolved solids. You're constantly adding stuff to the water, so of course it's going to continuously go up. And the stuff you see puffing up on your floor isn't dissolved, so it's not the source of dissolved solids. Chlorine, acid, baking soda, calcium, stuff like that is contributing to the TDS.

This is why we preach education and self-reliance over listening to the pool store. Their testing will have you fretting over completely normal things. Your phosphates are very low, but I'll bet they didn't tell you that. Time to give up the bad habit of pool store testing if you want to take full control of your water.

Since opening in May, the chlorine pool has remained clear and mostly a TFP thanks to the advice from this group, use of Taylor K-2006C and poolmath.
The chemical requirements have been mostly +2gal Liquid Chlorine about every week, with pH/Alkalinity/Hardness moving in and out of range when it rains, or having to add 500gallons of city water to counter evaporation (have a flow meter attached to hose), so I am letting them fluctuate instead of actively treating it with chemicals to reach a target level. I also add 3 tricolor tablets to the floater about every 2 weeks.

I often get the water tested at Leslies pool to have a read on Copper (0.5), Phosphates (116) and TDC (1400) (7/18/2023 values), however I follow the Taylor K-2006 and pool math app for any action.

Why this post? While the pool remains clear, I have noticed a slow increase in Phosphates and TDS and seeking advice if there is any indicated action to take.

Additional observations:
a) Prior owners did a poor job painting the gunite pool white, as the paint keeps flacking off every time the Dolphin Explorer E70 robot cleaner is used
b) Overnight test shows no Chlorine loss
c) The submerged walls, while no visible off-color, feel slick to touch, so I have began to brush the sides and floor with a pole/brush. Occasionally I noticed white clouds being formed when brushing the floor, suggesting some sort of floor deposit. (LIKELY THE SOURCE OF INCREASED TDS)
d) Backwashing every 2-3 weeks does not show much visible cloudiness
e) New variable speed pump running 2,900rpm 24/7 (have not tested variable speeds yet)

View attachment 512840

TDS is the total dissolved solids. You're constantly adding stuff to the water, so of course it's going to continuously go up. And the stuff you see puffing up on your floor isn't dissolved, so it's not the source of dissolved solids. Chlorine, acid, baking soda, calcium, stuff like that is contributing to the TDS.

This is why we preach education and self-reliance over listening to the pool store. Their testing will have you fretting over completely normal things. Your phosphates are very low, but I'll bet they didn't tell you that. Time to give up the bad habit of pool store testing if you want to take full control of your water.

Thank you and understand the feedback. I am only using Leslie's for the tests I don't run (TDS,Phosphate,Copper) for completeness. I am relying on TFP/Pool Math and not the pool store . As I continue to learn, and based on your comment, the filter would take care all the undissolved solids at some point via backwash and normal operation.
The other comments from the members indicate similar action. Thanks to all of you for your perspective.

 

[CMH-CVG]

-Some city water suppliers actually *add* phosphates to the water because it helps coat the inside of old pipes.
-Your TDS is everything in the pool to include salt, calcium, chlorine, skin cells, yada yada yada. Not a worry.
-Why is your Free Chlorine so low?? You're inviting algae to a party if you keep it so...... or you may well already have it since you mention slick floors Remember that pucks *add* CYA which means your FC requirements go up also. Keep your FC high enough to allow for the sun's daily burn off yet leaving you with enough coverage.
-You should be following the FC/CYA Chart-
-Only backwash when your filter pressure rises 25% over the clean pressure.

View attachment 512854

Maddie

Thanks. One of the differences I noticed early on with PoolMath and store results is the different ideal range limits each use, and that I'm using the PoolMath ranges for guidance.
I will adjust to reach a target Chlorine of 7-9 for the higher CYA levels I have, which have not reduced much.

 

[CMH-CVG]

TDS is a junk stat. It is mostly Calcium and Salt and has a wiiiiiiiiide range of possibilities. There's no telling one person that theirs is no good.

A TDS of 1900 (all calcium) would be an issue.

A TDS of 3000 (all salt) would be low for a salt pool and entirely fine for a liquid chlorine pool.

Disregard TDS, and anyone who pushes it.

While it's true that phosphates are algae food, it's a moot point if you sanitize properly so algae can't grow. If you don't sanitize properly, the unsightly algae you'll get is harmless. The bacteria, viruses and pathogens that'll also flourish are the worry, and they don't feed from the phosphates so again they're no concern.

Thanks, this helps my continuing pool education.

 

[Oly]

Test your fill water for TA, CH and pH so you can anticipate the effects of topping off during the summer. Use Pool Math to estimate your use of trichlor tabs and the changes to your pH and especially your CYA ppm in amounts not readily detectable with the CYA turbidity test. Keep your FC well into the target range. Needing to utilize the SLAM Process is no vacation in a 30,000 gallon pool with a high CYA.