I haven't backwashed since August 2019


Gold Supporter
Oct 5, 2019
Hey y'all, the title says it all. I've been waiting for my filter pressure to rise either from the "green arrow" to the "white arrow" or to simply go up 25%. It hasn't done either. When I bought the house last year, I read somewhere I was supposed to backwash monthly, which I did pretty faithfully regardless of the filter pressure. Then I was reading about how I should wait until the pressure rises 25%. I have been doing that now, and I noticed my pressure hasn't really moved since August.

The pool water is clear and colorless, except I can see some white particles floating in the water at night when I have the submerged pool light on. I have a manual vacuum which goes to a dedicated vacuum line, and it works fine too. There aren't any leaves or debris shooting out of the returns.

Is this typical?

In hindsight, this seems like a long time to go without a backwash. I'm thinking I should take apart the filter and make sure there's nothing wrong with the filter itself, especially since I'm supposed to do that yearly anyway. Thanks again for your help in advance!


Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
Bedford, TX

I have two rent house pools that have DE filters.. I never backwash any more.. I just break the filter down twice a year and clean them. Works great for me. I run a VS pump at about 1200 RPM so that is one reason that I can do that.

Not sure how you can do it if you have a single speed 1.5 HP pump unless you have a screened in pool. :scratch:

I can't see any reason for anyone to backwash once a month.


Jim R.


Gold Supporter
Oct 5, 2019
I do have a screened in pool. The 1.5 HP motor is on an intermatic timer and runs for about 4-5 hr / day. Yes the gauge on the filter returns to zero when the power is off.

Rattus Suffocatus

Silver Supporter
Jun 5, 2019
Corona de Tucson, AZ
I've not cleaned my cartridge filter since the pool was built in September and there is only a sight change in pressure from when it was new (literally a couple of PSI). But I don't have a lot of vegetation near the pool either so it might sort of be in a birdcage. I plan on cleaning the filters in the next weekend or two regardless. But yeah, I have the same issue or non-issue. I guess I will find out.


Gold Supporter
Jun 18, 2014
Glassboro, NJ
In 2017 & 2018 I deep cleaned my sand filter at opening. I went all year w/o backwashing. Did not deep clean last year because I was going to use DE and then back wash but did not. Ended up backwashing only one time. I used skimmer socks in 2017 during pollen season. 2108 forward i used disposable hairnets. Keeps alot of stuff out of the filter.

I use the TFTest oil filled gauge. New one last year. Forgot to takeoff at closing in 2018.


Bronze Supporter
Nov 30, 2019
Pawleys Island, SC
I have not backwashed ever since the pool was installed at the end of last summer. No more than a couple of pounds pressure rise. I asked about it before here on the forum I believe, not unusual. I use skimmer socks and a hose leaf filter for the vacuum so I guess the filter stays pretty clean.


Bronze Supporter
Jun 26, 2015
Mesa, AZ
I started using hairnets in both my leaf catcher in my cleaner line and in my skimmer, and I don't have to backwash nearly as often. I was thinking of switching from a DE filter as I didn't like the DE buildup in the yard, but now I backwash rarely enough that I'm not having any issue with buildup.


LifeTime Supporter
Jul 13, 2012
Dallas, TX

My info:

15k Gunite Pool. It doesn't get a lot of shade during the day. There are no main overhanging Tree Branches over the Pool.

Standard Chlorine Pool (no SWG).

Chlorine Dosing: TFP Method. I use 10% Bleach.

CYA Level : 50

DE Filter: Nautilus (Stainless Steel Tank) 36 Sq Ft DE Charge.

DE Charge : New or Cleaned Grid set: 7 scoops - using a Leslie's blue scoop - 1 scoop = 5 Sq Ft, approx 1/2 Lb
Subsequent Charges after Backwash : ~80% of a new-Grid charge, 6 scoops.

Multiport Valve

0-30 PSI Glycerin-filled Gauge

"Flovis" Flow Meter

I use both gauges to determine my Backwash frequency.

I don't use Skimmer Socks except when adding CYA.

I clean my Pump Basket once a week, daily Skimmer Basket Check/clean.

I usually average ~3.5 months between Backwashes with ~8 months my longest time.

When Backwashing, I run 10 Cycles with my Multiport Valve, with 1 Cycle = Backwash/Rinse action. I run 10 Cycles to get as much of the used DE out of the Filter as possible. After the 10th Cycle, my Sight Glass shows virturally no DE/Debris remaining.

I recently had to pull my Grid Assy on 09/25/19 due to a couple of tears in 3 Grids. Prior to that, my previous Grid Pull/Clean was 6 years ago. During that time, with the old Grid Set, my "clean" (starting) PSI after a DE Charge had risen ~3-4 PSI over the 6-year period.


Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
I do have a screened in pool. The 1.5 HP motor is on an intermatic timer and runs for about 4-5 hr / day. Yes the gauge on the filter returns to zero when the power is off.
I would venture to guess that the reason your filter pressure hasn't risen that much is the lack of debris in it.

Maddie :flower: