New user needs help with very old filter system

[Castle]

Hello!
I have a 20,000 gallon vinyl lined pool built in about 1965 and the filter system is pretty old.
I have been in the house about 4 years and have had little trouble until this year. I never have been able to get the pool water clean and algae free despite multiple shocks and "green to clean" treatments. It's August 3 and I have yet to get in the pool.

I have begun thinking the major issue is the filter system.

It is a fabric cartridge system from "Hi-Perm"



Anyway, it used to be that when my filter got to about 20 PSI I would have to change it and now it never gets past 10PSI - so I'm thinking either the inserts have some serious weak spots in them (there are 4 and I get the same result regardless of the one I use) or that there is a fundamental problem with the filter equipment itself.

I was just cleaning the pool and watever algae I suck up through the vacuum is coming out through the pump outlet and back into the pool

Anyone have any experience with these filters or should I just call it a day and get a new filter system. If new, what should I choose?

thanks in advance

 

[duraleigh]

Welcome to the forum.

I have begun thinking the major issue is the filter system.

I stopped right there and read no further. Filtration only filters non-living debris from your pool....it has nothing to do with the presence or removal of live algae.

Live algae exists because you have inadequate chlorine in the pool. Please read "The ABC's of Pool Water Chemistry" up in Pool School.

When that is all digested, read "SLAM - Shock Level And Maintain" in the How To section of Pool School. SLAMming your pool will be required but you'll have to give us some valid test results before you start.

 

[Castle]

I don't have a thorough test kit, I've always just used the test strips.

Right now FC is 4, alk 100, PH 7.2

I'm going to get a better kit tomorrow

 

[Charlie_R]

The better kit you need is likely not available at any pool store.

We recommend the TF-100 or Taylor K-2006, from http://tftestkits.net/splash-page.html

These are available from other online retailers, however shipping can be problematic from them. TFtestkits almost always gets your order out the same day if ordered in the AM, never more than out the next day for shipping.