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luvapool
03-31-2006, 08:55 AM
I will be getting an IG pool of approx. 23,000 gallons(US). Builder is sizing me with 150 sq. ft. cartridge but I think it is too small. What would be the correct size for my pool? I want to clean it as little as possible. Pool would only be operational about 5 months/year. I was sized a 1 hp. single stage pump as well.

CarlD
03-31-2006, 10:20 AM
I will be getting an IG pool of approx. 23,000 gallons(US). Builder is sizing me with 150 sq. ft. cartridge but I think it is too small. What would be the correct size for my pool? I want to clean it as little as possible. Pool would only be operational about 5 months/year. I was sized a 1 hp. single stage pump as well.

Not sure about the filter--the pump is fine, but try to get a 2 speed 1 hp (full rated, not up-rated).

Builders LOVE to talk people into cart filters. The first season you do NOTHING but then you find out what cleaning is involved. If you don't get soaked to the skin and filthy, you are probably doing it wrong. Replacements are extremely expensive--$75 to $150 so cleaning is a necessity rather than replacement. Still, some folks swear by them, others swear at them. I'm not an expert but the sizing sounds correct. Better to have too big a filter than too big a pump.

Why aren't you going with sand or DE? Have you considered them and ruled them out? Or did the builder just say "Oh, you don't want them..." and you are trusting his judgement? (He seems to have gotten the sizing correct so he probably does know what he's doing...). The plumbing is slightly simpler on carts, too--unless you get a 6-way valve that allows you to vacuum to waste.

kaybinster
03-31-2006, 11:16 AM
I would go with DE, it filters the best and is cheap to maintain. Also, bigger is better :) The bigger it is the more surface area it has and the less often you will have to clean it or backwash it.

duraleigh
03-31-2006, 01:46 PM
"luvapool",

there is another thread running with virtually the same questions. Search on "poolmikecalif" as the thread starter and you should find it easily.:)

Dave S.

waterbear
03-31-2006, 02:03 PM
Here is another thread with filter info. What type of filter should I use?
(http://www.poolforum.com/pf2/showthread.php?t=197)

luvapool
03-31-2006, 03:23 PM
I have no options for the filter. Town code requires a cartridge filter.
My SIL has a cartridge filter that they clean every week and I have the same builder. I am waiting to find out how big hers is. If it is 150 I am definitely upsizing.
Thank you for all your responses.

PoolDesignnet
04-02-2006, 03:47 AM
Luvapool,

What brand filter is your builder proposing? See if you can get a Hayward Swim Clear 225 s.f. It's a great filter and you won't have to clean is as often and will work fine with a 1HP pump(up-rated)

Zina
www.pooldesign.net

kaybinster
04-02-2006, 08:45 AM
I have no options for the filter. Town code requires a cartridge filter.
My SIL has a cartridge filter that they clean every week and I have the same builder. I am waiting to find out how big hers is. If it is 150 I am definitely upsizing.
Thank you for all your responses.

Where are you located? That is very strange that they require one type of filter - do you know why that is? Do they prohibit others, or just require a cartridge? If the latter, just install a tiny cartridge unit AND a DE unit and don't use the cartridge system.

waterbear
04-02-2006, 12:04 PM
Where are you located? That is very strange that they require one type of filter - do you know why that is? Do they prohibit others, or just require a cartridge? If the latter, just install a tiny cartridge unit AND a DE unit and don't use the cartridge system.
I read somewhere on the net that certain townships are requiring cartridge filters becuase of the water used to backwash a sand filter uses more water than the water needed to clean a cartridge. Don't know if itl's true or not but that is the reason. BTW, backwashing a DE filter is not a good idea, you will lose some DE but you will not know how much and could end up putting way too much DE back in and end up cramming the tank full of DE or not enough and therefore clogging the grids with dirt! The only way to know how much DE needs to go back in after a backwashing is the break it down and clean it. Breakdown on them is a REAL mess. Give me a cartridge any day! they will actually filter better if they are a bit dirty. Sand tends to channel and DE just stops filtering when they get dirty. A sand filter can filter particles from 60 to maybe 25 microns in size. A clean DE can filter particles under abut 6 microns but once it gets dirty it just develops too much pressure to filter well. A cartridge will filter to about 20 microns or less depending on how dirty the cartridge is. A slightly dirty cartridge filter will actually filter almost as small as a DE filter which is why some people put some DE into their cartridge filters after cleaning them. As you can tell I am a cartridge filter type of guy. Takes me about 10 minutes to hose it off including breakdown and reassembly once a month or month and a half. Yeah, the cartridges are pricey. Mine is $110 (Pentair Clean and Clear 150)and the one I had on my old spa was $65 but given the lifespan of about 5 years that doesn't work out to that much per year.

SJohnson
04-02-2006, 04:25 PM
For what its worth, I'm putting in a 550 sqft. cart. filter on an 18k pool. It's the largest I've seen and made by Hayward. I'm also going with the 1HP NorthStar by Hayward. From my research, it should be a good pairing. At least I hope it will be, time will tell how much it needs to be cleaned. My wife just wouldn't stand for backwashing, go figure. I would have put in a sand filter had she not been so obstinate.

waterbear, am I correct in assuming that de can be poured into the skimmer to get it into a cart. filter? I've heard of people adding it for sand, but not cartridges.

-SJohnson

waterbear
04-02-2006, 05:02 PM
Yes, you only need a little bit, maybe a cup or 2 depending on the size of your filter. It will increase your pressure and you might have to clean it more often but it will make it more effecient at filtering smaller particles. I prefer not to use it myself.