Sand vs. Cartridge Filters

[s1njin]

Hey Gang,

I'm debating my wisdom/choice of going w/ a sand filter vs. a cartridge filter. Reason being is all the water/money I'm wasting backwashing into the woods; especially when I'm doing a SLAM. I'm really wondering if I could have done myself a favor by opting for a cartridge filter. Also, I'm guessing by its very nature of needing to be disassembled to clean, a cartridge filter system should be much easier to sterilize in the case of the dreaded mustard algae? Could one simply take the top off, remove the filters, and douse everything inside with bleach and rinse it all out?

I'm open to the idea of switching to a cartridge filter once I get to the point when my sand needs to be replaced. Since they have to come out anyway (my plumbing is so torqued down for little drip leaks I loathe to strip all the PVC trying to remove it myself), I might just switch the whole thing out.

Thoughts?

Also, do cartridge filters typically run at a lower PSI than sand? My filter has ALWAYS been running at 19psi 'fresh', 14-15 psi on a backwash.

 

[Jimrahbe]

I would not base your decision on slaming, as once you get your chemistry set up, you should never have to slam again as long as you follow the recommended FC levels. Also a cartridge filter has no multi-port valve, so you can't dump to drain or bypass the filter if you want. I doubt you will save much water as you have to use water to clean the cartridges.

Jim R.

 

[gwegan]

I have a cartridge filter in California with serious water restrictions.

Some thoughts: If you get a large cartridge filter you will get slightly clearer water and only have to clean twice a year. Cleaning takes about an hour and involves spraying off the cartridges with a spray nozzle. I don't use more water because I turn off my lawn for a few days.

Sand filters are simple and they vastly outperform any other filter when you get algae.

Pressure numbers depend on your system. But have you deep cleaned your filter.

 

[ping]

A cartridge filter would be more work than a sand filter during a SLAM as you would need to take it apart to clean the grids.

You will save water by going to a cartridge filter.

Sand very rarely, if ever, needs to be replaced in a properly cared for sand filter. Once a year deep cleaning of the sand keeps it in good shape along with balanced water will ensure that the sand will last the life of the filter itself.

Cartridges usually need replacing every few years.

It takes longer for a sand filter to clear all the dead algae during a SLAM than a cartridge filter.

The biggest mistake of all is buying an undersized filter for your pool. If any filter is undersized for the pool, it will be a lot of work to keep the filter operating like it should.

 

[KazzyK810]

Prior to this pool (2nd year with it), I always had cartridge filters. Personally I like the cartridge. It was a single big cartridge though; about 30 inches tall and about 9 inches wide, so when it was full of water, it was a bit heavy to lift out of the housing. (Hayward Star Clear C-1750) I pulled it out once a week and hosed it off and put it back in. I bought a new filter every each. The filter from the previous year I kept to open with the following summer and didn't use the new one until I'd got the water completely clear. It was really so easy to take care of! The pool installer (fiberglass pool) said that my lot was perfect for the cartridge as it was full sun and had no trees. I also liked the I could carry the filter to anywhere I wanted to hose it off. So I'd clean it on areas of my lawn that looked like they needed a bit of water anyway. I wasn't losing any pool water, and didn't have to top up, so it didn't mess with my chemicals, and I liked that.

Now, new (to me) house and new pool with sand filter. I'm not a fan of backwashing. I don't like losing water out of my pool and having to top it up. But my pool is tiny, so a bit of water seems like a lot. Maybe a sand filter on a big pool is different?

They both kept the pool equally clear. Never had an algae issue with either. I've only had (or will have) a chlorine pool, so have never used a mineral system or a saltwater system, so I don't know if that makes any difference either? I've also never lived in a heavy treed area.

As to water usage, it takes quite a bit of water to really clean a big filter, probably as much as I lose backwashing, so personally, I wouldn't consider that to be a deciding factor.