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Mwmcgee
05-23-2012, 11:36 AM
New member here, I've been looking for some info on your threads but did not find what I was looking for so I thought I'd post a question.
Basic info, I have a 20k gallon pool, kidney shaped, with DiamondBrite finish. A 2hp pump drives the water through a Hayward cartridge filter. I change out the filter and clean the cartridge twice a week since they tend to clog quickly and the pool becomes cloudy. This is especially true in the summer when the daily temp is in the upper 80's and we get a lot of rain. I don't currently have an automatic vacuum but I vacuum and sweep once a week. I have the local store (where I get my chlorine) check the water every two weeks and I add a jug of chlorine and some tabs weekly.
I'm looking into changing out the cartridge for either a sand filter or a DE filter. I already have a selector valve installed with true union fittings so changing is a snap. In researching the filters I find that the DE will be less expensive initially but, if I backwash regularly, the DE media will run up the cost. Alternately, the sand filter is more expensive initially but the maintenance costs are very low. I am mechanically inclined (I changed out the pump when the old one froze up) so I'll probably do the work myself unless I get a really good deal locally.

So, which filter would you recommend?
Is there a specific model that is better than the others?
How do I determine the size I would need to effectively filter the pool?
Will either one work well with an automatic vacuum if I get one?

Thanks for the assistance. If you need more info, either post or contact me directly.

Watermom
05-23-2012, 05:23 PM
I just recently replaced my pool for a larger one. Ben and I were discussing sand filters and his preference is either a Pentair or Hayward. With 20K, you would probably want a 24" filter. Here are the links he sent to me. See if either one of these would work for your pool.

http://www.a1poolparts.com/-strse-1499/Pentair-Triton-II-Fiberglass/Detail.bok

http://www.a1poolparts.com/-strse-1480/Hayward-Pro-Series-Side/Detail.bok

Your pump is pretty big. You really don't need such a big pump. When it comes to pool pumps, bigger is not better. A too powerful pump can force debris too quickly through a filter without filtering it out. It can also cause damage to the filter.

Someone else may chime in here on this thread with more opinions on this. I am not the equipment guru by any means, but this may at least give you a start.

Welcome to the Pool Forum by the way!

Mwmcgee
05-23-2012, 07:58 PM
Watermom,

Thanks for the links, those are helpful.

The pump was a direct replacement for one that was installed when the pool was refurbished around 10 years ago. It pushes thru the filter but also feeds two small returns and a waterfall.

Thanks, Mike

Mwmcgee
05-31-2012, 07:11 PM
Just so I understand, what is the difference between a DE filter and a sand filter? How often does a DE filter have to be back washed? A neighbor owns a sand filter and regularly back washes (once a week) and has never had to add sand, is this typical?

Thanks for the assistance.

Watermom
05-31-2012, 07:37 PM
DE filters have diatamaceous earth in them as the filter media which is a very fine powder. Sand filters obviously use sand as their filter media. DE filters filter out smaller particles but are higher maintenance. I do not know how often DE filters need to be backwashed as I do not have one. Sand filters are the easiest to maintain and in my opinion, filter just fine. All of the moderators on the forum have sand filters however many of our other contributing members have DE or cartridge filters and like them a lot, too.

In a sand filter, you should only backwash whenever your filter pressure rises by 8-10psi over clean filter pressure. It is not necessary to routinely backwash once per week. You don't have to add sand often but every few years you may need to top it off. One misconception is that sand needs to be replaced and this is not true. It seldom needs to be done. I am on the 12th season with my same sand.

Mwmcgee
05-31-2012, 07:43 PM
I'm in south Florida so our season is year round. We require less filtration in the winter due to the cooler temps, more in the summer.

I think I'll probably go with a sand filter, now I need to check the local stores for a good deal.

Thanks, Mike

waste
05-31-2012, 08:11 PM
Welcome to The Forum!

Please check out this (http://www.poolforum.com/pf2/showthread.php?9189-cleaning-a-DE-filter) sticky for some info on DE filters.

While I would have a DE filter, I've got a lot of experience working on them - IMHO, sand is the easiest to use and maintain.


All 3 kinds are fine, but any pool owner needs to ask questions and find out which one will best suit their pool. ;)