Consistently Low FC Levels with AutoPilot - Are High Phosphates to Blame?

[bostondad21]

Hello! I am grateful for any help here - I feel like I've been running in circles and have gotten opposing answers from local pool stores and experts I've consulted.

I have a 26k gallon, vinyl liner pool with AquaCal AutoPilot DIG-220 with a PCC 1 salt cell

I had the salt generator installed late last season, so this is really our first time using it. This season, the pool has been crystal clear, but FC levels are consistently low - I have a LaMotte SpinTouch lab and consistently get between 0.2 -0.8.

Trying to troubleshoot this issue has driven me mad. Test results showed a normal PH (7.3-7.4), ALK of 100, Hardness of 170 (working on increasing to 200), CYA of 100, and Phosphates of 4500.

• The pool company who installed the salt generator, and AquaCal are convinced Phosphates are the issue, and that I need to lower them to under 500PPB or lower. I threw a whole bottle of Lo-Chlor Lo-Phos into the pool (half one day, half the next - washed the filter between), and the readings are now in the low 4000's high 3000's for phosphates.
• My other pool company claims that phosphates are not the issue (and reading through TFP it seems that the community would agree?).
• I hired a 3rd party expert to consult with me, and he recommended adding Boric Acid to the pool, and also said I needed to control the phosphates by following the procedure on a phosphate remover product until levels are reduced. He suggested I shock the pool by maintaining a high level of chlorine of 25PPM for 48 hours, which seems a bit excessive and concerns me about bleaching the liner.

I feel like I'm going in circles with competing/conflicting advice from experts, and feel like I'm making the problem worse. Am I overthinking this issue? Is my problem of consistently low FC levels related to high phosphate readings?

Thank you for any help - if you're a professional and have the answer, I'd gladly pay you for your time.

Thanks to all!
Boston Dad

 

[bostondad21]

A couple of other things to note.

The AquaCal rep took me through the settings on the AutoPilot to review everything was correct. It was set at power level 1 (he recommend 2, so we changed it) and it was configured for a PCC 3 cell, not the PCC1 I have (thanks to the installers). He also said the PCC1 cell is at the upper limit for what my pool should have. Not sure if any of these settings will help, or if they make any impact at all, or if I should be upgrading my cell to a PCC2 or 3.

 

[Katodude]

So a bunch of things.

First Welcome!!

We would recommend a better test kit. The TF-100 is the best you will get. Get a speedstir with it.
Your FC is low because you most likely have algae. If you CYA is really 100 (again better test kit will give better results) then you FC is too low and algae has taken hold (it can be invisible) and that is eating your FC as fast as your SWG can make it. Vicious cycle. You will need to SLAM in order to do that (need a good test kit to do that).
You have a vinyl pool so CH does not matter. Unless its too high that will affect your SWG.
Phosphates dont matter. Treat them if you want but thats not your problem.

soooooo

Order a new test kit.
Then read this.

ABC's of Pool Water Chemistry

There are several items things every pool owner should know about swimming pool water. We share details on the basics of Pool Water Chemistry.

www.troublefreepool.com

Then this

SLAM - Shock Level and Maintain

We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.

www.troublefreepool.com

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