Inline series filter possible? Sand then DE?

keithtx

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Jul 29, 2007
8
I was just reading the DE vs. Sand filter thread. Great info; thanks. I am planning a 30-40K gal. pool/spa & wanted to maximize dirt filtering capacity (minimize backwash) due to lots of pets & even free range chickens which lose lots of feathers etc. Was interested in using the 3.2kw Intellitouch & pump.

Wondering if you can series a large 36" sand filter flowing into a Quad DE 100. Was thinking the sand would p/u the large stuff & the Quad DE would polish off the small stuff thus extending backwash/maintenance. Would that be too much pressure drop/electricity? If it is oversized for the flow rate it seems like the added pressure would not be too bad.

Any equipment advice for an ideal system would be appreciated! Need help figuring this all out!
 

Hotrod30

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keithtx said:
even free range chickens which lose lots of feathers etc.
Sorry..... I had to laugh at this. That is something I don't have to worry about. Mice... moles....snakes....rabbits..... but no chickens.

I run an undersize sand filter (Hayward S200) for my 30,000 gal pool (filter will be changed this summer) and a DE filter that I run half the output from the sand filter threw. The pressure went up a couple of pounds (clean) but not bad. Alot depends on piping, bends (45 deg and 90 deg), valves and how many returns you are using. When I charge my DE filter, I just put the sand filter on recir. It sounds like you are planning a 20 X 40 foot pool with a spa.

As for the Pentair IntelliFlo Pump, that's sitting in my garage; will be installed this summer. I'm not sure what to expect from that.
 

duraleigh

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Keith,

The sand/DE combo in series is something that's always seemed a good idea......I just wonder about the cost/benefit. You would take on the maintenance of two filters and the up-front cost of two filters for a fairly small improvement in your water quality.

I do like the idea in theory but I wouldn't do it in my pool. The filter I have does a nice job (sand) and I would not be willing to pay the extra price and additional maintenance required.

If the size of your pool is pretty well set, then you can size the equipment accordingly. Generally, you should have enough pump (gpm) to turn over your pool 2-3 times in a 24 hour period. Your filtering capacity should exceed the pumps capacity by 25% or so. If you're going to have a spa or waterfall or other features, they must be taken into consideration, too.

So, once your pool plans are set, you'll get lots of help sizing the equipment and thoughts about multi-speed pumps for your particular situation.
 

keithtx

Member
Jul 29, 2007
8
RE the dirt; plan on having the pool edge raised about 16" to help keep dirt out & so you can sit on the edge like a bench. We have peacocks too and 6 dogs. Think I need a lower fence around the patio just to keep these critters away too (entire yard already fenced). One time a chicken blew into the koi pond and died. It was very windy that day so she lost her balance and could not make it out. The koi pond I did myself with some help. 1800 sq. ft. gunite x 4' deep. Did the plaster myself too: 2 layers, mortar based type w/ additive. That took a lot of gunite trucks and was about a 2 yr. project.

The pool will be 25 x 50' x 4.5' avg. w/ a spa. About 42,000 gal. Kind of tired of looking at systems & just need peoples advice at this point. Pretty sure will go w/the Intelli system components. I read about how to clean the DE filters in the other post. How is cleaning the Quad DE different? Seems like this one is quite different. I am afraid it will get clogged too quickly w/DE so was thinking adding the sand filter 1st would be a good idea just like in a multistage water filter. Get the big stuff first then get the finer debris. Overall this should not add much to the back pressure GIVEN the same amount of dirt put into the system it may well be less since it is spread out over 2 filters. Thus one is not backed up/clogged like one may be.

Thanks for your input!
 

SeanB

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At work (chem plant), we use 20 micron fiber cartridge filters, before going into 7 micron stone filters. This keeps us from having to change the stone filters very often. For us, loss of flow, means loss of prime production so the cost is justified. I can't imagine a scenario where dual, in line filters, would be financially justified in residential pool care - especially where the end results is negligible at best.
 
G

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using skimmer socks in your skimmer basket would me a much more cost effective prefilter, IMHO.
 

keithtx

Member
Jul 29, 2007
8
The skimmer sock goes w/i the skimmer box? Never had a pool. So do most people use a sock or no? Is it possible to have a larger basket that comes out (vs. sock) like those in the pump strainer basket but w/ even more surface area? Kind of like a french fry basket at McDonalds. Those pump baskets get full w/very few leaves. I have that on my koi pump...
 
G

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my pool is the same measurements but DEEPER, so i have aTON more water to filter, i must say that the 400 pound sand filter i have does an AWSOME job filtering. but when i upgrade im gunna go to DE as i want the more finer filtering. so what ever your willing to pay for is what you should get, their both good filters.

DE filters better but requires alot of work to keep it going

sand filters good and needs almost no work once installed, just backwash once a week, and your done.

de needs to be backwashed also but you have to add DE every time you do, sand you dont need to add anything after you backwash.
 

duraleigh

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just backwash once a week, and your done.
Backwashable filters, both sand and DE, should be cleaned (backwashed) when needed. This will depend on how much debris has accumulated in your filter. You may go weeks without backwashing or you may have to backwash more than once in 24 hours if you're filtering an excessive amount like during an algae bloom.

Generally, a very good indicator of the need to backwash is a 20-30% rise in the operating pressure of your system.
 

JasonLion

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A skimmer sock goes in the skimmer basket. The skimmer basket is very much like the pump strainer basket except larger and inside the skimmer.