DE filter with a sand filter

[quacka]

Was wondering.....if I currently have a sand filter, would there be a benefit or disadvantage of having a DE filter downstream? Seems that sand filter would catch most, prolonging DE. Thoughts?

 

[Bama Rambler]

The down side would be the added head loss of adding the additional filter. If you're not happy with the filtering that the sand filter is doing you should first try to figure out if something is wrong with the filter. Or if it's something going on with the water. What does the water look like?

 

[quacka]

Water is clear, as usual, thanks to TFP. Was just wondering as I saw a great deal on a DE filter and thought about adding it to my system.
Since pool is enclosed, I rarely have to backwash sand filter but was wondering what's the life expectancy of sand? i understand it can become 'polished' but wasn't sure if I would start seeing particulates in the water or how I would really know it is time to change sand.

 

[pwrstrk]

I don't have a sand filter but from what I've heard on the forum is the sand doesn't go bad and shouldn't need to be replaced under normal circumstances ?

 

[Smykowski]

Sand existed for millions of years before it went in the filter, so it won't go bad. There are a very few scenarios where sand needs to be replaced, but those are outliers.

You can deep clean the filter once a year by opening it up and gently pushing a running garden hose to the bottom. Move the hose around very carefully (so as to not break a lateral). This will kick up the sand and dislodge the gunk down low, plus allow for a resettling of the sand bed later. Let the water run and overflow from the top until the junk stops flowing out. Reassemble, rinse, and you're good to go.