Phosphate levels? Who's testing?

Heavenlytunes

Silver Supporter
Oct 25, 2020
175
Nassau, Long Island NY
Pool Size
20000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Autopilot Digital PPC1 (RC-35)
In the month of August I struggled with low chlorine. 0.5 to 1.5 pmm.
Everything was good just a little high CYA but dropped some water and replaced.
Using Pool Calculator App. Was back on track but still low chlorine 2ish...
Someone mentioned phosphate so I order a kit and tested for phosphate yesterday.
I had to brushed every 2 days if not I can see algae creeping up.
Can phosphate be my problems?
Anyone knows why two cards for measuring?
Thanks
 

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I have to brushed every 2 days if not I can see algae creeping up.
Can phosphate be my problems?
Never once have I checked for phosphates. You see algae "creeping up" means you need to SLAM.


 
Recommend you use the PoolMath app or old PoolMath link at bottom of pretty much every page in this forum. The Pool Calculator is just not as accurate as PoolMath.

I see you aresharing your PoolMath logs, but the last log was over a month ago. In that log, given your listed CYA, your FC is way too low. Use liquid chlorine and dose according to the FC/CYA Levels.

How are you regularlychlorinating your pool?

Fill out your signature with pool, pool equipment (including make and model numbers) and test kit info.

Phosphates aren't really an issue if you maintain your pool water to TFP standards.
 
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Everything was good just a little high CYA but dropped some water and replaced.
Using Pool Calculator App. Was back on track but still low chlorine 2ish...
Someone mentioned phosphate so I order a kit and tested for phosphate yesterday.
I have to brushed every 2 days if not I can see algae creeping up.
Can phosphate be my problems?

Once you get a new set of test numbers, set your FC levels to the corresponding CYA levels in the following chart: FC/CYA Levels

You might want to consider another drain / refill to bring that CYA level down slightly

To answer your question directly, phosphates are widely considered as "algae food," so they might be feeding the pesky growth you're noticing when you brush. But that won't matter if you put the proper amount of chlorine in the pool to kill the current algae and prohibit further growth. Nobody here worries about them, tests for them, or uses chemical or draining to remove them. We just don't let algae grow.

If you've got algae, SLAM the pool and keep your FC levels above the minimum for your CYA.
 
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How are you regularlychlorinating your pool?
Nice catch. With their salt level at 3400 and a previous CYA of 70, I'd guess it's a SWCG. Unsure why the CYA went to 90 in 2 weeks' time unless there's some pool store / trichlor shenanigans going on...
 
In the month of August I struggled with low chlorine. 0.5 to 1.5 pmm.
Everything was good just a little high CYA but dropped some water and replaced.
Using Pool Calculator App. Was back on track but still low chlorine 2ish...
Someone mentioned phosphate so I order a kit and tested for phosphate yesterday.
I have to brushed every 2 days if not I can see algae creeping up.
Can phosphate be my problems?
Anyone knows why two cards for measuring?
Thanks

Using the card with 0-1000 range, the sample tube should be held on end as the graphic on the right side of the card indicates (ie you should be looking down through the sample tube, not from the side).

Using the card with 9-6000 range, you are holding it correctly.
 
Nice catch. With their salt level at 3400 and a previous CYA of 70, I'd guess it's a SWCG. Unsure why the CYA went to 90 in 2 weeks' time unless there's some pool store / trichlor shenanigans going on...
Do I need to be chlorinating the pool? I thought thats the whole reason of the SWG.
I'll re test today and log in the results.
I kind of gave up the past 2 weeks and knowing they're doing the winter cover this Saturday.
I'll start fresh next year with lots of new water.
 

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SWGs are good at maintaining a safe level of chlorine, but they'll likely not be able to get your pool sanitized if you've got something growing. That'll still take regular additions of liquid chlorine. I don't know how to close down a pool, so unsure if it's wise to try to fix the algae issue before they cover you up this weekend.
 
My phosphates were crazy high when I moved in to this house. I never had an issue with chlorine loss that couldn't be explained by an algae bloom or some other issue. That said, I had specks of black algae that I could NOT entirely eradicate no matter what I did. For the heck of it, this year I bought some PR10000 and removed the phosphates right before I converted to SWG. This summer, the specks of black algae were much easier to fight, and they haven't been returning like they were, even with LESS brushing. YMMV, but I do test it now and will continue to do so. It may not be considered necessary to remove phosphates, but it did seem to make a subtle difference for me.
 
My phosphates were crazy high when I moved in to this house. I never had an issue with chlorine loss that couldn't be explained by an algae bloom or some other issue. That said, I had specks of black algae that I could NOT entirely eradicate no matter what I did. For the heck of it, this year I bought some PR10000 and removed the phosphates right before I converted to SWG. This summer, the specks of black algae were much easier to fight, and they haven't been returning like they were, even with LESS brushing. YMMV, but I do test it now and will continue to do so. It may not be considered necessary to remove phosphates, but it did seem to make a subtle difference for me.
I bought some of that PR10000 waiting to get here. Will give it a shot and bring it down to Zero.
 
There are many pools out there that are affected by phosphates, but they are the very slim minority. Just throwing a rando # out there, but half a % of 12 million pools is still 60k pools. It does matter at times but to openly discuss and approve it on the forums as a regular thing does a disservice to the oodles of new folks coming in grasping for straws thinking /praying/hoping that they could be the one. Especially when the pool store already got it in their heads that it’s critical for all. Statistically speaking they aren’t even close to being the one.
 
If you're having problems holding chlorine that's highly indicative of algae. Pools with active algae problems need to get those under control before attempting to reduce phosphate levels, otherwise you could end up with a big mess. Most removers specify this on the instructions, it's not just a TFP thing.

Follow the SLAM Process until all 3 criteria are complete. Then if you wish to mess with your phosphate level have at it.
 
I don't know if you can see it but those at the spots that I get every day. I brushed them yesterday. Came back today
 

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When I converted to SWG's this year I also could not get my FC up. The SWG manufacture told me one thing to do was to test for phosphates, as this was the likely culprit. I bought the same test kit as you. First test was 50 (they said to try to get it to 0)! I added the required amount of phosphate remover. Second test: 100! When all was said and done, phosphates were not MY problem. I had this pool since 1986 and NEVER tested for phosphates before, and probably never will again!
 

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