Pump backwash this morning, flow slowly dwindling... help?

Apr 29, 2016
19
San Antonio Texas
Pool Size
14500
Chlorine
Liquid Chlorine
Per installer of pump one year ago, we completed back washing as needed and only disassembled to clean filter after one year. We installed the same filter that we had installed at our previous property. We have experience and success with this filter and pump. After cleaning the pump 4 weeks ago, the pump is slowing sooner, requiring backwash sooner. Today, I backwashed the filter and flow was good, but perhaps not amazing, phosphates were at 500 due to a pool party yesterday. I treated with PhosFree/NoPhos per instructions, reduced alkalinity 20 points and shocked the pool with 1lb cal-hypo. By evening the flow was barely visible on surface level. Ideally, backwash again 48 hours from addition of NoPhos.

Thoughts? Just seems like filter is already saturated.

Thanks for any help of thoughts!
 
Do you still have the test kit you said you ordered a couple years ago? Post up your test results.

The phos free is a cheap clarifier. So it will plug you your filter.
 
Testing and treating for phosphates is a dead end street. You will get no meaningful results until you ignore phosphates and understand that it is chlorine that will keep your pool pristine.

Stay OUT of the pool store and post your own current test results. We'll all help get the pool crystal clear and filter running correctly.
 
Good morning! Thank you for responding... I have been able to avoid pool store for quite a while...

As of this morning:

PH 7.0 (after lowering alkalinity to 80 (using Tayor, this lowered more than expected using calculations FYI)
Chl 7.0 after 1 lb hypo cal approx 24 hours previous with 0 chlorine
Alk 80
cyan 50
Not sure about phosphates... but if not going to focus on them... is it necessary to test?

This pool last year I rarely had to had chlorine during the summer.
Previous pool I slammed and followed procedure and it was good.

Seems like where I need to go at this point as well as increase PH after knocking down alkalinity.

Thanks for your help!
 
Your pH will rise naturally. And TA is of no issue. It will fall as you keep your pH in the 7's.

Focus on maintaining FC as per the FC/CYA Levels

I see you use cal hypo. What is the CH of your water? What is the CH of your fill water?

Can you add what test kit you use to your signature?
 
Ok!

Just competed all tests again so up to date at this time of day.
FC 7.0
CC .5
TC 7.5
PH 7.0
CH 500
CYA 50
H2O Temp 87
SI -0.25

Water source shows no calcium present - water purifier/ whole house including outlet used from exterior kitchen wall
Water system install appox 1 year ago... not sure that high calcium prior to new water supply would keep it high. Perhaps CalHypo.
 
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We will believe your tests. We do not recognize pool store tests.

You should consider getting a FAS-DPD test kit to more accurately measure FC and CC.
 
Apologies... again.. see what happens when the pool doesn't have issues FOREVER and then... :(
I added the FAS-DPD to the kit I purchased because it was the only thing missing, I knew it was the difference between good and variable info.

Agreed with pool test scores.. so when phosphates were a consideration I decided to find out how to test them and purchased the necessary vile etc. Unfortunately, I really couldn't determine what the color on the bottom was and had to ask the store to help. I do understand... bad results+coached solutions=increased profits for stores.

I had our pool on cruise control for about a year and when I couldn't resolve the chlorine usage etc., I panicked. So unlink me :)

I will retest CH tomorrow with chlorine, ph etc. We will see what that CH looks like again.

Thank you!
 

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Ok. Here is where we are at this morning.

FC 5.0
CC 1.0
CH 450
PH 7.2
TA 90
CYA 50
Temp 87
SI 0.00

Pool continues to bust through chlorine. Crazy backwash late yesterday with a bunch of water added which I believe adjusted the CH.
Pool looks much better, but still need to stabilize FC. Recommendations on shock or slam? Keep the faith with hypo-cal or straight up chlorine?
 
With your CH you should not be using cal hypo.

Your test yesterday showed a FC of 7, this morning is 5. That is not much of a drop for one day. What do you mean by 'bust through chlorine'?
 
Ah... so perhaps my expectations? Last year... the chlorine was so stable it was rare to need to add it. Maybe dropped 1 ppm in the course of a week or longer. Held the range.. for a couple weeks easily. Perhaps I was just spoiled last year. Also, and perhaps the other point being is that when you slam a pool, you are keeping it at a certain level until there is very minor loss of chlorine from nightfall to morning so when I see 2 ppm in a day.. I am thinking there is something consuming it more rapidly. I have a steady amount of roley poley's in the pool this year. We use to refer to them too as potato bugs. I was informed that they are present when there is something to consume as well.
 
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the chlorine was so stable it was rare to need to add it
Sorry to be a spoilsport but that just can't happen.

Please review "The "ABC's of Pool Water Chemistry" up in Pool School. We have to get you on the same page with us before we can help you appreciably.

In Pool School, you will find chlorine is a daily consumable item.....normally 1.5 - 2.5 ppm each and every day for an outdoor pool.....maybe a bit more more in a climate like San Antonio.
 
Not a spoiled sport at all. But thank you for your concern :) I used TFP and pool math without issue until this year when something changed and I couldn't figure out it if it was more debris, etc. For personal reasons I was flying north about every 4-5 weeks since January and I sense that my inability to be here and present I put me into a spin with how to proceed. I would assume that how stable it was last year and then into winter where there is less maintenance put me into a less focused state regarding testing beyond the daily group of FC/TC, PH, TA. For whatever reason, this year had been much more challenging, had some algae and just never seemed to get to a more stabilized sanitation level. Going to move toward liquid shock for a bit to reduce CH and test more regularly on CH, CYA etc...
 
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