Replacing cartridge with sand

[dansdad]

Is it possible and worth doing to replace my Hayward cartridge with sand filters? I heard they are better but I know nothing about it

[Watermom]

I can't help you with how to replace it but will tell you that sand filters are WAY easier to maintain. I think you'll be glad you switched!

Welcome back to the Pool Forum for another season!

[BigDave]

I'm with Watermom, I love my sand filter. That said, why do you want to change?

[dansdad]

pool isn't all that clean and I read where sand is better but I don't even know where to start. If I have to backwash, don't know what to do and would have to be repiped which is not a problem. I just don't know if Im opening a can of worms Im going to wish I didnt

[BigDave]

What kind of cartridges do you have? Many cheap knock-off carts don't do the job no matter how much they cost. Filbur, Unicel, or OEM are the only ones recommended here: Recommended equipment for new inground pool (http://www.poolforum.com/pf2/showthread.php/22981-Recommended-equipment-for-new-inground-pool).

[Watermom]

The advantage of sand over cartridge is the ease of cleaning the filter. For a sand filter, you simply turn a handle on the top of the filter a couple of times. The whole process takes about 2 minutes tops. Simple, simple. Personally, I will never have anything but a sand filter.

[kelemvor]

I was under the impression that cartridge filters smaller particles that sand does not. Am I mistaken?

Cleaning my cartridge probably takes 10 or 15 instead of 2.

[dansdad]

my cartridges come from my pool store and I believe they are unicel

[BigDave]

If you have quality carts that are in good shape and you're still unhappy with water quality you could try using polyquat 60% to see if it helps filter some of the smaller bits.

An oversized sand filter will filter better than a smaller one (as long as it can be backwashed). With sand you can also polish the water with a little DE to catch finer bits than the sand can by itself.

Some parts of California have water use issues. Is water use limited where you live? Sand filters require occasional backwash - dumping water which must be replaced.

[dansdad]

I'm not sure of the water quality Dave but I do have a fresh bottle of 60% polyquat here. I will give it a try. Thanks one Dave to another

[BigDave]

Earlier you said that the "pool isn't all that clean" is the reason you are considering filter change. I thought that meant water quality (to me: little tiny stuff in water that makes it look dull). Did you mean something else by clean?
No thanks needed (but appreciated), I like to help.

[Watermom]

No thanks needed (but appreciated), I like to help.

And, Dave, we appreciate all the help you do give! Thanks!

[BigDave]

Right back at you Lisa.

[dansdad]

what I meant was sometimes the filters seem like they don't do enough to keep the pool free from debris. The sweep works fine. Thanks, Dave

[CarlD]

You could either have inferior brand cartridges, you are not cleaning them correctly, or your cart is too small for your pump.
A properly sized cartridge filter, properly maintained, should perform better than a sand filter but not as well as a DE filter.

Most people here don't like them because they are tricking to clean, but those who figure out how to clean them well, and with little effort, swear by them.

[dansdad]

I have decent cartridges but I need to find a better way to clean them. I saw a device where you lay the filter down in a tray and run the spray nozzle over them, plus I may need to get rid of a couple. How long are they supposed to last if cleaned twice a year? Thanks to all Dave

[BigDave]

Have you seen PoolDoc's thread on Cleaning your Cartridge Filter without Damaging It! (http://www.poolforum.com/pf2/showthread.php/18044-Cleaning-your-Cartridge-Filter-without-Damaging-It!?highlight=cartridge+filter+clean)?

[kelemvor]

I have decent cartridges but I need to find a better way to clean them. I saw a device where you lay the filter down in a tray and run the spray nozzle over them, plus I may need to get rid of a couple. How long are they supposed to last if cleaned twice a year? Thanks to all Dave

Twice a year? I clean my cartridge weekly during the summer and fall. Twice a week in the spring. Once a month (roughly) in the winter.

I've never had a cartridge get ruined but after about a year the "clean" filter pressure ends up about 10psi higher than the "clean" pressure was when I bought it. I replace mine roughly every 18-24 months.

[dansdad]

just as you mentioned it, I looked and ordered cleaner for the cartridges. Will be ready for summer. Thanks Dave

[mas985]

Twice a year? I clean my cartridge weekly during the summer and fall. Twice a week in the spring. Once a month (roughly) in the winter.
Your cartridge filter is obviously way too small for your pool. A properly sized cartridge system should only need to be cleaned once per year. Also, frequent cleaning is probably the reason you are replacing them so often. I have had my cartridges for 8+ years, clean them only once per year and the filter pressure never gets more than 1 PSI above the clean filter pressure.

I am also one of those people who would never trade a cartridge for any other filter type. I just think cleaning it once a year is far easier than backwashing many times per year (my parents had a sand filter).

[CarlD]

The usual rule for backwashing a sand filter is when the pressure goes up at least 5 lbs. I'd guess it'd be the same for cleaning carts.

[dansdad]

let me say the filters are the same size that cane with the pool. I have never changed the size. I have 4 cartridges that barely fit in the housing so there is no room for bigger. I only clean about 2-3 times a year. Im going to clean them with cleaner and wash completely. My filters are Unicel, so no cheapies there. I'm hoping by through cleaning each time it will get better

[mas985]

5 PSI is over 11' of extra head which can significantly reduce flow rate in a pump no mater what filter type. For example, with your pump (Carl), if your normal operating point is 54 GPM @ 40' of head, at 50' of head, the flow rate would drop to 40 GPM going from 50' of head to 60' of drops it to 9 GPM! Personally, I would not let the filter pressure rise more than about 25% of the clean pressure to keep flow rates up. But then again, if that meant backwashing every week, I might stretch that.

Dansdad,

My size comment was regarding kelmvor's comments. But is sounds like you have fairly large filters.

[dansdad]

Thanks got responding I think I just need to replace my filters as there are two from the original setup and pool is 7 years old. I'll start fresh with new filters and then keep them clean

[Shredhead]

I have two sets. I use the old set for opening and change it out after two weeks. Then my good set lasts about 2 months.

[dansdad]

does everyone s cartridge filters last before being replaced? one season? 2 years? I'm really wondering

[mas985]

I have one set of cartridges going on 9 years now.

The only reason you should need to replace your cartridges is because they are torn which is often caused by cleaning or they are so clogged that you cannot clean them anymore which is often caused by bad chemistry. So the key to extending the life of the cartridge is keep the chemistry in balance and avoid algae blooms (I have had one in 9 years), and go with a large filter to minimize cleaning and the chance of damage. Also, a small pump helps to reduce the flow rate through the cartridge filter.

[dansdad]

thank you ...im getting a plethora of info here