Filter Style Sanity Check

Strom

Platinum Supporter
LifeTime Supporter
May 18, 2009
28
Greenwood, Indiana
We currently have a sand filter. Actually that's all we've ever had on the pools we owned. So last year I upgraded my pump to a variable speed. The sand filter seemed to be fine. But I'm thinking about changing to a cartridge filter. Then I think about a DE filter. Then I think I'll post something on the forum and see what others would do if they had a 16x32 in ground salt pool.

Any and all opinions welcome. Thanks.
 

pooldv

TFP Expert
Platinum Supporter
LifeTime Supporter
Moderator Emeritus
Aug 10, 2012
25,412
FL panhandle
I have a cartridge filter and it is fine. We have lots of trees dumping debris in the pool in spring and fall. Sometimes I think it might be nice to have a sand filter to backwash more easily rather than having to take my filter apart to clean it 2-3 times in spring and fall. DE is not on my list, too much extra work for not enough better filtration. My pool water is already so clear that I really don't think it is possible for it to get clearer.

Here are a couple of articles from Pool School that might help
Pool School - Pool Filter Comparison
Pool School - Maintenance and Cleaning of Pool Filters
 

triptyx

TFP Guide
Apr 12, 2016
1,512
Tucson, AZ
I'm with pooldv. I grew up with a sand filter, and being able to just crank the handle and backwash was nice compared to having to take apart the cartridge filter I have now. I'll agree I enjoy the better filtration on the cartridge myself over the sand.

DE just seems like far too much of a hassle, having to replenish the earth nearly every backwash, grid problems, etc.
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
12,733
Houston, Texas
Personally I would stick with the sand filter unless water replacement is an issue. I've had a DE filter that I had to open up and hose out when it needed cleaning. They really don't backwash very well. If you have a lot of fine debris that gets caught in the filter you will be cleaning and recharging more often, depending on the size of the filter. If your sand filter works well and you don't have to worry about water restrictions or topping off with iron laden well water I would just stick with the sand filter. To me the outcome doesn't justify the expense. If you do decide to go with a cartridge filter have a waste line plumbed in just in case. It is very handy in case you ever need to drain some water.
 

BattleOfYakima

TFP Guide
Apr 15, 2016
1,682
Central Florida
I've worked with both sand and cartridge, but not DE. For me, when looking towards future pools, I only see cartridges. Here's my thinking so far:
Cartridge:
1. Cleaning cartridge takes time, but i listen to audiobook or music, so I use the time well
2. On the few times when I slip up and get some green, I can have it crystal again in a few short days.
3. During the 350 days a year my pool is absolutely perfect, it is as crystal clear as is imaginable to me or any of my many guests (I don't have a pool light, so I can't speak to the particles that might be visible at night, don't care)
4. I get a really nice peace of mind that the filter is clean because I can see it with my own eyes after each cleaning
5. No water loss during cleaning YAY!

Sand: (***My sand filter was undersized*** so keep that in mind when reading these, and when buying yours, don't skimp)
1. During clean up after a green swamp - constant CYA loss during backwashing was annoying and costly, took weeks to get crystal
2. went from a couple PSI away from backwash time to backwash time real, real fast, like sometimes a few hours
3. Take this one as a bonus if you're a fisherman/woman - when backwashing, dozens and dozens of worms come to the surface
4. But so does all the nastiest water you've ever seen flooding over wherever you backwash, including particles that made it through your skimmer and pump baskets
5. Lived in constant fear that spider gasket/gear would fail - man I was broke then and that would have been a hardship
6. Had the pipe that leads down to the radials stick to the top when removing it once, and pulled the radials out by accident, risking damage
7. have to be careful when deep cleaning or risk damaging radials
8. Had the occasional fear that my sand was settled in some places, making pathways of least resistance, not actually filtering optimally - wow I was a worrier back then!
9. Positive - had the option to try adding DE or Cellulose Fiber if I ever wanted to
10. Maybe positive - if I had to ask someone to maintain my pool for an extended time - backwashing might be less to ask a neighbor than closing the valves, pulling and taking the hose to a cartridge

Assumptions that exclude DE for me:
1. Would have to buy that box that traps DE on backwash because I refuse to dump it on lawn or put in stormdrains/sewer/septic
2. Would have same water/CYA loss issues during backwash
3. Why am I spending more/complicating things when I've achieved a crystal clear TFP with both sand and cartridge?
4. Might really consider it if I had a seriously illuminated nighttime pool and I was bothered *IF* I was unable to get the results I wanted with cartridge or sand

Final thoughts:
1. No matter what you go with, make sure it is BIG enough for the pool you have and the debris that you expect to have to deal with - especially if you live in a windy area/trees/flowers/dirt/pollen!
2. Unless you have seriously strong feelings - or just want to switch - your money might generate more happiness for you if you invested it, paid off debt, did some extra self care, donated it, or whatever - both sand and cartridge (with appropriate size and flow) are ridiculously low maintenance ways to keep a pool filtered and I'm grateful to their inventors/improvers
3. Anyone else helping take care of the pool? Would sand be easier on them? I know lifting a large cartridge can be harder on the weak, elderly, or those with joint issues compared to turning a dial to backwash.
4. If you go cartridge, I suggest the investment in a $6 fireman style brass hose nozzle
5. If you live in a water-restriction or high chlorine cost area - cartridge wins, no contest for me
6. If your pool is a perfect storm of pollen and dirt blown in - maybe sand saves you time on maintenance overall?

- - - Updated - - -

If you do decide to go with a cartridge filter have a waste line plumbed in just in case. It is very handy in case you ever need to drain some water.
I totally agree! Not necessary, but I've wanted this feature a few times during hurricane/rain season when it overflows and further floods/erodes the surrounding area instead of the corner of my property where I'd rather it go
 

kadavis

TFP Guide
In The Industry
Apr 5, 2015
1,651
tucson, arizona
Might look into the Pentair Quad DE filters. They do suggest a backwash valve, but I'm starting to see some installations without the valve. They come in larger capacity then normal and basically resemble a cartridge when you open up. Very similar in size to the Clean & Clear plus filters
 

stevie3x

In The Industry
Feb 17, 2017
37
laguna hills , ca
they all have pros & cons , first the sand filter does not filter as fine of particles as the other 2 , and almost always need backwashing weekly, thus loss of not only water but where you have a chlorine gen sys you lose salt & cya. you can add a floucculating agent for better filtering however it must be added again after backwashing, at some point the sand will have to be replaced , a real pain. however all in all an easy to use filter.
second the cartridge filter works well filters smaller particles , easy to clean, however when the element gets impregnated with dirt it is extremely difficult to clean completely, and when the filter starts collecting dirt it restricts the flow of water to a degree ,
the de filter filters the smallest particals , is easy to backwash, however it is harder to disassemble to manually clean all the internals , most mfg. recommend taking apart 1 or 2 X per yr. and the de can be dificult to get rid of, our code says the waste must be plumbed to the sewer, not a septic tank or out on the ground or down the drain or to the street.
 

borjis

LifeTime Supporter
Aug 19, 2014
3,342
Pacific NW
they all have pros & cons , first the sand filter does not filter as fine of particles as the other 2 , and almost always need backwashing weekly
Backwashing weekly?

I back wash maybe 2 times a year. at most. As do many others. Maybe you lived in the dust bowl?
 

ping

TFP Expert
LifeTime Supporter
Jun 24, 2011
3,138
Long Beach, CA
Here's an article that might help out if you haven't read it yet, Pool School - Pool Filter Comparison.

There's no simple answer as to which one would be best for your pool as each filter type has pros and cons for each situation. Too small of filter of any type will be the worst decision that can be made so make sure you get the largest you can afford and install on the pad.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
17,530
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I have a Pentair QuadDE filter for my pool and it's oversized. It works perfectly and is a great filter to own. I don't ever backwash anymore, I just tear it down twice per year. I personally think it's a step above the old grid-style DE filters (Pentair FNS series) and it's really a no-brainer when it comes to maintenance. The only downside to it is that the internal quad cartridges that the DE sticks to (they look just like cartridges that you would put in a cartridge filter) are expensive to replace when they wear out, about ~$120 a piece and you need 4. But, if they are well cared for, they should last a lot longer than standard cartridge filters because the element is only there for the DE to adhere to it, it's not doing any filtering itself (that's what the DE is for).
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
17,530
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Might look into the Pentair Quad DE filters. They do suggest a backwash valve, but I'm starting to see some installations without the valve. They come in larger capacity then normal and basically resemble a cartridge when you open up. Very similar in size to the Clean & Clear plus filters
I've thought about removing my backwash plunger-valve but realized they are actually useful even if you don't backwash regularly - it's good to backwash first before you open the filter to tear it down. It helps to backwash first to remove a lot of the old bulky DE that weighs down the quads. After I backwash, then I open up the filter and clean it all out.
 

domct203

Bronze Supporter
LifeTime Supporter
TFP Guide
Jun 3, 2015
3,959
CT
If you are backwashing weekly either you have too small a filter, or are continually fighting algae.

My old Intex 14" sand filter would go for two or three good vacuums (pool is under two large trees) before needing a backwash, which was about every 3-5 weeks.