High Pressure, Low Flow?

[SwimmingGirl]

Hi All! We have an 18' above ground pool. We have a hayward DE filter and our water is clear, and tests well. We use EZ Pool instead of traditional chlorine.

Here is our problem: Since the pool was installed last summer, we have a hard time with the water flow out of the filter. The pressure starts at 16 and goes up to 20 or 21 and the flow slows down to barely moving the top levels. We go out and pump the filter, and its good for a few hours, then it slows and we repump and it fixes it temporarily. We have back washed it - and the first time it was pure green with pollen from the pines, but after that initial time, we backwashed it and the water was clear. We didn't add more DE because our pool place said maybe there is too much DE, but we followed directions when we opened the pool this summer. There is no blockage because when we vacuum we have a huge suck - enough to collapse the hose. Please help! thank you in advance.

[Denniswiseman]

Filter is blocked
Let's have your numbers
FC:
TC:
pH:
TA:
CH:
CYA:

[act10x]

Hi There! did you get an answer for this? I have the same issue, when filtering, I have normal pressure on gauge, but the water low is super low, in backwash or rinse, the flow is great as always

[Teapot]

In backwash or rinse you are not filtering so you wont get the same flow. Backwashing needs to be a higher flow to clean the media. Rinse does flow the same path but out to waste and are you using DE?
DE filters fine particles compared to sand so it also clogs quicker until you filter out all the dirt etc and this includes particles you cannot see without a microscope. This is the price you pay for excellent filtration, lower flow as dirt builds up. The filter is doing its job.
Most domestic setups and filters do not backwash properly this means the filter silts up over the seasons and changing media is often the quickest way to restore the filtration, cleaning thoroughly is another.