Pressure increase at gauge over time, resulting in low pressure out of the return

[jsc219]

Hi TFP,

I am a relatively new AGP owner, as on 2019. I have a Hayward DE finger type filter and a 1.5HP pump. I am have an issue over time with pressure. Ideal pressure on the filter is 10 P.S.I. When I first opened the pool last year and this year and added DE, 5 scoops, to the filter, the pressure is 10 P.S.I. and I see normal strong pressure from the return. Over time, the pressure value goes up and by the time it reaches 20 P.S.I. I see greatly reduced pressure from the return. I am priming the filter daily and that helps for a little time, but the starting P.S.I. generally starts higher each day and gets to 20 P.S.I sooner. I backwashed the filter after a month and added 4 scoops, and that returned P.S.I to 12, not 10 for a short time and now I am back up around 15-20 P.S.I. priming the filter daily. I am trying to figure what to do next. I am trying not to waste DE by doing another backwash. Last year, I had the same problem. Last year, the only way to get it back to 10 P.S.I. was to open the filter and completely wash it out and start over. I have shutoff values on both sides of the filter to do so. That said, I wondering if there is another solution to this problem rather than opening the filter and completely rinsing it out.

Couple side questions:
1.) Should I use 4 or 5 scoops of DE? The manual says use 5, but my installer recommended 4.
2.) Should I have to prime the pump daily? I am and that does seem to help initially But over time the pressure gauge goes up / pressure goes down from the return.

Any advice would be greatly welcomed and appreciated.

Sincerely

Jeff

 

[ajw22]

Welcome to TFP.

What test kit do you have?

How do you chlorinate your pool?

Please create your signature with details of your pool and equipment.

Your description is usually signs of algae in your pool building up and clogging your filter. Clear the algae and you fix your problems. You can confirm the algae problem by doing a Overnight Chlorine Loss Test. Then the SLAM Process to make your water algae free.

I suggest you read ABCs of Pool Water Chemistry and

What is TFPC?

We believe any pool owner can achieve and maintain safe, crystal clear pool water, by using the science-based, Trouble Free Pool Care (TFPC) methodology.

www.troublefreepool.com

 

[Richard320]

Yep, what he said. Classic symptoms of a nascent algae bloom.

 

[jsc219]

I use three things to chlorinate the pool:
1.) Opening the pool, I used 2 gallons of liquid chlorine (from Walmart); adding more when my chlorine levels go down.
2.) I have chlorine tabs in a chlorinator after the filter. I generally keep 1-2 in there at all times.
3.) And use HTH super shock ever once in a while.

As for tests, I am using two types of pool strips; one with CYA and one without. I know from this forum these tests aren’t the most accurate but I haven’t bought the more expensive / higher quality tests yet.

As for it being algae problem, I did have a big issue with that last year. I left the pump off for 3 days and came back to an emerald green pool and had algae problems afterwards last year.

This year, I haven’t see too much visible algae. That said, after bumping my filter and turning it back on, the water from the return is green at least at first, and then it clears up. So, is it possible that I have more algae in my filter than in my pool?

 

[ajw22]

You can have algae with the water being clear. Non-visible algae will clog your filter over time as you are experiencing.

Get the TF-100 Test Kits or the Taylor K-2006C and follow our process and you can clear up your problems and have a Trouble Free Pool.

It's up to you which direction you want to take.