DE vs cartridge filter

[rjb1211]

As I work on my plan to upgrade equipment I wasn’t giving much thought to the type of filter. I have been very happy with my current DE filter and just figured that is what I would get again.

I went to a brick and mortar store to see what their pricing was going to look like and they automatically included a cartridge filter. When I questioned it they said that is what everyone gets these days; the DE type is old school.

I only need to backwash once or twice a season and I replaced the grids once in the 31 years I have had it. Articles I found on filters rate DE as the best for filtration.

Is there something to what I was told or is it typical pool store misinformation?

 

[Bperry]

As I work on my plan to upgrade equipment I wasn’t giving much thought to the type of filter. I have been very happy with my current DE filter and just figured that is what I would get again.

I went to a brick and mortar store to see what their pricing was going to look like and they automatically included a cartridge filter. When I questioned it they said that is what everyone gets these days; the DE type is old school.

I only need to backwash once or twice a season and I replaced the grids once in the 31 years I have had it. Articles I found on filters rate DE as the best for filtration.

Is there something to what I was told or is it typical pool store misinformation?

Cartridge all the way. I’d pick a sand filter over DE of those were the only two choices.

 

[Newdude]

Articles I found on filters rate DE as the best for filtration.

It's bragging rights only IMO. Your yard drops crud and that crud traps finer crud inside the filter. You can change filter types but your yard crud is a constant.

There's about a 5 micron difference between the 2, millionths of a meter, or 1/25,400 of an inch each. Good luck spotting those.

 

[RLP]

Im very happy with my DE filter. Backwash once a season, and the water is crystal clear.

Of course, I have no experience with a cartridge filter.

 

[Jimrahbe]

rjb,

Here is my story that I have repeated many times...

I have two rent house pool that have DE filters. So, when I built the pool at my house, I really, really wanted a DE filter. But, my City will not allow DE unless it is plumbed into the sewer, which we could not do, so I was "forced' to go with a large cartridge filter...

That was about 9 or 10 years ago... Not going with DE is the best thing that ever happened to me... No one on earth can look at my pool and tell me what kind of filter I have. Cartridge filters have dirt simple plumbing, no backwash or MPV to leak or go bad, very low back pressure, and the best thing, not having to deal with DE. People that love their DE filters are stuck in the past, and have never used large cartridge filters.

If I built 10 more pools they would all have large cartridge filters.

The key, in my mind is having a large VS pump combined with a large cartridge filter. I could go a full year, or more, between cleanings, but I clean the cartridges twice a year. Once in the Spring and once Fall. In normal operation, I only have about 1 lb. of filter back pressure using a 30 lb. gauge.

If I lived in a location where the pool was closed in the winter, then I'd only clean the filter at closing. Cartridges last 8 to 10 years. The larger the filter the better.

Thanks,

Jim R.

 

[rjb1211]

Thanks for the feedback.

If I start to get algae one of the steps in getting rid of it is to backwash the filter. With the cartridge design do you take it apart and clean it?

 

[Newdude]

Yes, you should clean any filter after an algae break, but if you follow the FC/CYA Levels, its a non issue.

I honestly don't get it. So many people shortchange their chlorine and then pay more and have way more headaches (VS none) in the long run.

 

[rjb1211]

Yes, you should clean any filter after an algae break, but if you follow the FC/CYA Levels, its a non issue.

I honestly don't get it. So many people shortchange their chlorine and then pay more and have way more headaches (VS none) in the long run.

No matter how hard you try, sometimes stuff happens.

 

[rjb1211]

How do you go about sizing a cartridge filter?

 

[ajw22]

I think it is personal preference which set of hassles and convenience you prefer.

I like having a MPV and its various functions. And I like being able to backwash my DE filter in about 15 minutes with no tools required.

My DE filter is broken down and cleaned at closing every Fall and I backwash it two or three times during the season.

 

[an1vrsy]

When I started our owner/build in 2020, supposedly, Las Vegas didn't allow DE unless you jumped through hoops. I guess that could have been what Jim said above about plumbing, whatever. So based upon TFP best practice, I ordered the largest cartridge filter, Pentair 520, I could.

I like the cartridge filter a lot. Our last pool in California had DE. I never backwashed it, I would once every 18 months disassemble it, remove the grids, rinse them off, reassemble, recharge DE and call it a go. Now, with a cartridge filter, and a second pair of filter media, it's open it up, swap out the dirty with the second set, then reassemble. I could then rinse off the dirty cartridges at my leisure.

Long story short, I would select the largest cartridge filter for your pool, after experiencing both DE and cartridge filtration.

 

[AQUA~HOLICS]

Both.

 

[Newdude]

How do you go about sizing a cartridge filter?

With 33k gallons you want the biggest of any style filter. For cartridges that's 500+ sq ft. I don't think anyone could ever notice the difference between the 500 and 540 of different brands because the 500s will go all season.

 

[Jsf721]

I don’t have any experience with a cartridge filter however I really like my DE filter. Attaches extremely fine particulate even phosphate, debris that my buddy Sand filter blows right back into the pool.

 

[bradgray]

Both.View attachment 530471

Real talk.

All you have to do is swap the intake bulkhead baffle and bottom manifold with the CCP adaptations and you've got yourself a cartridge filter.

You could arguably not even do either of those things, and it would still work. But the flow is better with the proper swaps.

We also remove the handle from the MPV or Push/Pull so you don't have a stranger blow up the cartridges.

Keep the two sets of parts and you can use one or the other style based on how you "identify" at any given moment.

 

[gkw4815]

I have a cartridge filter and am happy with it overall. I will say that the inability to backwash is a downer when fighting algae - I had to break down the filter and clean the cartridges weekly while fighting a nasty algae issue early this past summer.

As long as the algae is kept at bay, and as long as I keep manual vacuuming of the pool to a minimum (which I can do now that my Polaris 280 is working properly), I only need to clean the cartridges 2-3x a year.

 

[Bperry]

I have a cartridge filter and am happy with it overall. I will say that the inability to backwash is a downer when fighting algae - I had to break down the filter and clean the cartridges weekly while fighting a nasty algae issue early this past summer.

As long as the algae is kept at bay, and as long as I keep manual vacuuming of the pool to a minimum (which I can do now that my Polaris 280 is working properly), I only need to clean the cartridges 2-3x a year.

Fighting algae…you can take the filters out until it’s dead and then replace them to clean up. That is one downside I guess, but it’s mostly preventable downside.

 

[Newdude]

I had to break down the filter and clean the cartridges weekly while fighting a nasty algae issue early this past summer

Were you seeing a PSI rise or just cleaning them just because ? (Big fan of just because btw).

I ask because I cleared a black swamp with 500s on a 35k gallon pool and when I cleaned them after (just because) they were far cleaner than after a regular spring on a heavily oak-d property. I also cleaned them every spring, just because, but never *needed to*.

Your 460s should go all season on 25k gallons, pretty much no matter what.

 

[gkw4815]

I only clean them in response to psi increase (which I measure with my VSP running at max speed - psi reads 0-1 psi at my standard 1300 rpm no matter how dirty the cartridges are). Whatever type of algae I was fighting earlier this year was really plugging them up fast.

~15 psi increase correlates pretty well to the appearance of "check flow" error messages on the heater when running my spa, which I do at 2600 rpm. So that's when I clean my cartridges.

This will be my first fall and winter with both a VS pump and a properly-working Polaris 280, so I'll be fine-tuning VS pump time and Polaris run time to try to keep the pool as clean as possible even as our mature trees are raining down leaves (pool stays open all year). This time last year I was manually vacuuming the pool weekly, but I haven't had to vacuum the pool once since fixing my Polaris 280 this past spring. I assume less manual vacuuming -> less work for the cartridge filter.

All that to say - I am hoping to to stretch my filter cleanings to once or maybe twice a year now that I've got the pool mostly dialed in.

 

[Newdude]

Hairnets/skimmer socks on the skimmer baskets stop most of the crud, greatly increasing cleaning intervals for any filter.