Which filter should I go with, Sand, Cartridge, or D.E.??

[JohnN]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

I would disagree with a cartridge being a PITA during opening. I close my pool, and when I open it in the spring I have no problems with my cartridge. If you close the pool properly, it shouldn't get too swampy, which would minimize cleaning of the cart.

 

[mas985]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

I just meant that it can be a PITA. There many posts on the forum of people in an endless cycle of cleaning their cartridges during an open. Yes, it can be done much easier but it takes some planning.

 

[linen]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

Since you live where you would close the pool and probably only keep it open for 3-4 months, you might get away with one cleaning per season if you get one large enough (~48 sq-ft). But for a winterized pool, clean up is easiest with a sand filter, DE next, and cartridge is probably the hardest.

I have a sand filter, swg and also winterize. I probably backwash my sand filter a about 10 times per year (a few times in the spring when I am opening and then about 1/month for ~ 5 months). That works out to losing [s:3b8he0o7]~2lbs of salt and ~13 oz of cya[/s:3b8he0o7] ~10 lbs of salt and ~4.5 oz of cya (see following posts for correction) the whole year on my 11000 gallon pool due to backwash amounts...not much. That amount is dwarfed by how much I have to add at the beginning of our season due to lowering the levels for winterization (I have to make up about ~20% of my water in the spring). Of course if you do not maintain the chemistry and you have to fight algae, then backwashing a sand or DE filter can use a lot more salt and cya than a cartridge filter.

 

[mas985]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

Linen, something isn't adding up. Assuming a 3000 ppm salt level, that is about 275 lbs of salt. Losing only 2 lbs of salt all season is 0.73% salt/water loss or only 80 gallons of water which is only 8 gallons per backwash. The 1 HP Matrix will produce about 50 GPM on high speed so that would be about a 10 sec backwash each time. That doesn't seem like very long. How long do backwash?

 

[linen]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

Let me check my math...When I backwash, I run for a little less than a minute. A bucket test I ran showed I am at about 47 gallons/minute (so I estimate 40 gallons). So if worst case, if lump all my backwashes together...i.e if I did 1 backwash for 10 minutes (verses the 10 backwashes for 1 minute with refills between) that would be 400 gallons out of 11000 (my pool volume). So (11000-400)/11000=0.964 So final salt would be 3000*0.964= 2892 ppm salt.

Yep I made a mistake, I would need about 10 lbs of salt and about 4.45 ounces of cya (made a mistake on that one too). oops...Thanks Mark! I have redlined my post above.

Bottom line though is that is not very much salt or cya.

 

[Soupy]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

I'm in Maryland, just north of DC. I can't imagine owning anything other than a sand filter. My back yard is wooded and the trees dump a lot of junk into my pool, and the sand filter is crazy easy to maintain and use. Carts and DE seem like a real pain in the rear to maintain and clean. Rain usually keeps the pool topped off so losing a little water to back washing isn't a concern, plus the tap water here is soft and clean.

 

[mas985]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

Bottom line though is that is not very much salt or cya.

I agree and it probably shouldn't be a determining factor for filter choice.

 

[chiefwej]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

A cartridge filter certainly can be a real PITA during an algae bloom. Breaking your filter open every day or two so you can change or wash down your filter is no fun.


A sand filter will take longer to clear the water, but back washing couldn't be easier. You can speed up clearing the water by adding a little DE after each back flush.

A DE filter in the same situation will much more quickly clear the water, and you just back wash to clean it. But you do have to recharge the DE (or fiber media) with each backwash.


BTW: Since I have a separation tank after my DE filter, I have the option of capturing my waste DE and returning the back wash water back to the pool, which means losing no salt, CYA or water.

 

[JohnN]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

How does the separation tank work? I guess the dirt gets trapped in the DE, and doesn't stay in the water? Now I am more interested in a DE filter.

 

[chiefwej]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

Seperation tank is just a tank with a bag inside that's made of the same material as that is used inside the DE filter. When you back flush the water flows backward from the filter carrying DE into the separation tank where the DE is captured in the bag, then the water can be directed to waste or back to the pool.

If you want a filter that's easy to live with its sand. The only drawback it has it that it doesn't filter quite as fine as the others, but a handful of cellulose fiber tossed into the skimmer solves that. Back flushing is quick and easy, no break down cleaning needed and the filter media last for years and years.

 

[msgtdan]

Re: Which filter should I go with, Sand, Cartridge, or D.E.?

I have a sand filter and have only backwashed once so far this year, right after opening. I have had to pump to waste to drain all the rain water we've gotten this summer. I'm going to have to add more CYA after this round of rain. The pool water has been sparkling clean all summer.