cartridge filter issue

Jun 13, 2012
I have an 24' above ground. We just got a new cartridge for our filter- A a hayward I think its ever clear 400. 40sq ft. Any how the pool pressure rises after only a few short hours. How long should I be able to run the filter with out having to clean the cartridge. BTW- our pool is very cloudy, have yet to see the bottom this season.

Thanks from Maryland


Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
Houston, Texas
The filter is doing its job, filtering out some of whatever is making the water cloudy. It sounds like you need to complete the shock process on your pool to clear up the cloudiness. For more information on the shock process read shocking your pool and defeating algae
After the shock process is complete the filter should go several weeks without needing to be cleaned.


TFP Expert
Mar 3, 2011
In addition to the shocking process, I would suggest getting a second cartridge so that you can swap out a dirty one for a clean one and then do a proper and thorough cleaning on the dirty one. ... _users.asp

Note: Most "TSP" is not real TSP (Trisodium carbonate). Real TSP works best, if you can find it.

Also, if you can post a full set of test results, we can better assist you.
Jun 13, 2012
thanks for the info. Im a little confused though. Do I just keep adding shock until I get the chlorine to the recommended shock level based on the chart? Im pretty sure our cya level is low. It was last week when we had the water tested and we havent been able to stabalize chlorine despite having floaters. Im going today for a test kit and a test. Will post results later.
Jun 13, 2012
so here are the test results.

saturation index .7
tds 600
cya- not tested (pool girl said cant test unless we have a FC reading. I tested CYA at home at got 30ppm
fc- 0
ph 7.8
tot. alkalinity- 173
hardness- 273

thats what Ive got!



TFP Expert
Mar 3, 2011
You are in the high-risk range for scaling. The high saturation index is probably contributing to the cloudiness. I suggest lowering the pH to 7.2 and keeping it at 7.2 until the TA comes down substantially. See this link for the process to lower the TA.


Next, you should maintain shock level until you pass the overnight chlorine loss test, your water is clear, and your CC level is 0.5, or less.



The cartridge is probably scaled and needs to be cleaned according to the directions here: ... _users.asp

You can use the pool calculator to calculate how much chlorine to use to achieve the correct FC level, how much acid to use to lower your pH, your saturation index, and lots of other cool stuff.
Jun 13, 2012
thanks- looks like a fun couple of days- hopefully not weeks. The kids will love a fountain. I guess I'll head to the hardware store! So I have pool store PH reducer. Will that work the same as the dry acid?