Question Regarding Phosphate Remover and FC Impact

[kundderek]

Hello - as some of my recent posts here have noted, I have chosen to delve into learning about / making adjustments to my pool chemistry. Armed now for the past two weeks with my Taylor K2006 and a new Jandy Aquapure SWG, I've been feeling pretty good about my work. I still have a pool guy but my own crisis of confidence about him had me learning all of this.

Over the past two weeks, I've been able to bring my TA down from a high of 180 to a manageable 70-80 with a pH of 7.6. Methodical MA adds got me here. I recently asked my pool guy to not add any chemicals to my pool. Told him he could test the water and let me know if he thought I should add something and that I'd look into it.

Over the past week (post July 4th pool party), I've seen my FC drop from 11 (July 5th), to 5 (yesterday July 8th am). Some of this is me trying to determine what the best SWG % setting is for my new salt cell. Had it at 50% ahead of my July 4th party and I started the day at a scary 17.5 FC, added water and brought it to 14.5, It was 10 by the end of the party.

My pool guy came yesterday. I got home from work and noticed my pool was very cloudy. Tested all of my levels:
FC 5.5
CC 0
pH 7.4
TA 70
CH 800
CYA 95
Salt 3400
CSI -0.13

Since my pool guy has been told not to add chemicals, I assumed the issue was my FC wasn't high enough. I ran my SWG at 'Boost' overnight, tested the FC again this am and only got a 0.5 bump in FC to 6. Added liquid chlorine this am (will test later) but the pool looks great here in the afternoon.

Texted my pool guy to ask whether he checked the cell for scale because it didn't appear to produce any chlorine over night and told him my water was pretty cloudy yesterday after he left. He replied "it was cloudy because I added phosphate remover". Ugh. Don't know why he did that and I haven't asked him yet. Kinda peeved that he didn't listen to my request to not add any chemicals. In any event I have a couple of questions...finally.

1) Could the Phosphate Remover have inhibited the chlorine production from my SWG? Maybe that's why boost only added 0.5ppm over a 12 hour evening?
2) I've read that because phosphate remover was added, I should now be cleaning my DE filter daily for the next few days. Just want to confirm that's true? I've never cleaned my own filter but I'm sure I can find some vids on youtube.
3) I know I should ask him, but why add the Phosphate Remover? There are no signs of Algae in my pool. Granted my K2006 test doesn't have a phosphate test but from what I've read here it's not one of the run-of-the-mill tests to perform. .

Thanks all!

 

[jark87]

I’m sure an expert will respond, but I’ve used phosphate remover in the past and it didn’t affect FC. It will make the water cloudy and depending on your phosphate level, it will probably settle as white dust at the bottom, which really needs to be vacuumed to waste. Yes, keep an eye on your filter, as the pressure will more than likely rise quickly. Personally, I’d ask the pool guy to do the cleaning until the problem is resolved since he didn’t follow directions. Your CYA is very high, especially for your FC level. I keep my CYA at 80, which is 10x my FC level of 8. I’ll err on the low side for CYA since the test is subjective.

As far as your SWCG production, you could have a failing cell or, more than likely, you have an algae outbreak. Try the OCLT. See info below. Good luck!

Overnight Chlorine Loss Test

This test is intended to determine if your pool has a contaminant such as algae … Read more…

www.troublefreepool.com

 

[reggiehammond]

FC/CYA Levels CYA 100 - Minimum 8 Range 11-13
You likely have algae - confirm with Overnight Chlorine Loss Test.

Your CYA and CH are much higher than you likely can live with... you should consider replacing at least 50% of your water to get to a place where the SLAM Process can be effective, and your CH can be manageable.

 

[Bperry]

I started the day at a scary 17.5 FC, added water and brought it to 14.5, It was 10 by the end of the party.

With your CYA so high, thats not at all scary. You can swim all the way up to SLAM level which is 39ppm when the CYA is 100ppm.

The issue is following the FC/CYA chart as mentioned above. You got the chlorine too low and the SWCG cant keep up when algae is growing. Always use liquid chlorine to boost the FC level and use the SWCG to maintain that level. They arent good at increasing is fast.

 

[kundderek]

I’m sure an expert will respond, but I’ve used phosphate remover in the past and it didn’t affect FC. It will make the water cloudy and depending on your phosphate level, it will probably settle as white dust at the bottom, which really needs to be vacuumed to waste. Yes, keep an eye on your filter, as the pressure will more than likely rise quickly. Personally, I’d ask the pool guy to do the cleaning until the problem is resolved since he didn’t follow directions. Your CYA is very high, especially for your FC level. I keep my CYA at 80, which is 10x my FC level of 8. I’ll err on the low side for CYA since the test is subjective.

As far as your SWCG production, you could have a failing cell or, more than likely, you have an algae outbreak. Try the OCLT. See info below. Good luck!

Overnight Chlorine Loss Test

This test is intended to determine if your pool has a contaminant such as algae … Read more…

www.troublefreepool.com

Thanks for the reply. Just tested the FC after having added the liquid chlorine this am and at a comfortable 10.5. I'm going to run the SWG at 100% for 6 hours just to see if it gives the requisite 0.5ppm/hr increase of 3ppm. I've got a reminder set for 9p to check FC, shut down the SWG for the night and do the overnight test. I'll report back tomorrow.

 

[kundderek]

With your CYA so high, thats not at all scary. You can swim all the way up to SLAM level which is 39ppm when the CYA is 100ppm.

The issue is following the FC/CYA chart as mentioned above. You got the chlorine too low and the SWCG cant keep up when algae is growing. Always use liquid chlorine to boost the FC level and use the SWCG to maintain that level. They arent good at increasing is fast.

Thanks for the reply. Ya, on the am of July 4th I did panic for a bit but soon saw previous posts on TFP that suggested everything would be fine haha. I've been of the 1/10th mindset where I try to target my FC to be 1/10th of CYA. Still learning but having a good time while doing so. Hoping I don't have an algae issue as it would be the first time that I'm aware of in my 7 years with this pool and just a week or so after asking my pool guy to let me handle the chemicals going forward.

 

[kundderek]

FC/CYA Levels CYA 100 - Minimum 8 Range 11-13
You likely have algae - confirm with Overnight Chlorine Loss Test.

Your CYA and CH are much higher than you likely can live with... you should consider replacing at least 50% of your water to get to a place where the SLAM Process can be effective, and your CH can be manageable.

Thanks for the reply. I'm waiting to do a water replacement or more likely renewal in the off-season and managing the chemistry in the meantime with PoolMath. It's that decreasing FC over the past week that threw me for a loop but as you and others have pointed out...algae is the likely culprit. I'll do the overnight test tonite.

 

[kundderek]

Shut the swg off 30 minutes ago. Pump will run overnight at 1400rpm. Just did my nighttime test for OCLT. FC = 12. Will see where I’m at in 8 hours. Good night.

 

[kundderek]

Shut the swg off 30 minutes ago. Pump will run overnight at 1400rpm. Just did my nighttime test for OCLT. FC = 12. Will see where I’m at in 8 hours. Good night.

Am piece of the OCLT 7.5 hrs later has me at FC = 12.