Diatomaceous Earth add

kalypso · May 29, 2020

my pool is currently nice and clear and the chemicals balanced ok. it is going to get hot here in phoenix this next month. my question is should i add any diatomaceous earth in to go through the filter? if so how much? i have tried to figure out previous questions and answers on this subject but the threads dont seem to follow each other..
thanks much

mknauss · May 29, 2020

As you have a sand filter, there is no reason to add DE to it. Some do to 'polish' the water of fine material, but if your pool is clear and nice, do not bother.

kalypso · May 29, 2020

thank you so much! all we mainly get is dust and some small biting bugs. i have added both the intex pool filter sock and also nylon stocking. these seem to catch some of the dust.

Jim Murphy · Jul 18, 2020

What then is the indication for DE? I have a problem with fine particulates (beetle poop) that is difficult to vacuum and and I am having a hard time cleaning it up.

Richard320 · Jul 18, 2020

Jim Murphy said:
What then is the indication for DE? I have a problem with fine particulates (beetle poop) that is difficult to vacuum and and I am having a hard time cleaning it up.

DE gets added to a sand filter because
1) Too many floaters in the light at night
2) Taking forever to clear dead algae during a SLAM.

It's like laying window screen on top chicken fire to sift out smaller particles, just on a microscopic scale. If there's a lot of small stuff, it'll clog up fast. Like within hours fast. But If beetle poop is making it through your filter, the DE powder likely would, too, and make a bigger mess.

Jim Murphy · Jul 19, 2020

Thank you for that. What would you say the typical interval is to open the filter and change the sand? or is there other filter maintenance (besides the obvious) that I should be doing. My pressure readings are right about 10 psi after backwashing, hence I am not seeing a problem. "Channels" in the sand??

mknauss · Jul 19, 2020

Sand, if not compromised by pool store potions, will out last the filter housing.

About the only maintenance to the sand is to deep clean.
Read Sand Filter Use and Care - Further Reading

Richard320 · Jul 19, 2020

Jim Murphy said:
Thank you for that. What would you say the typical interval is to open the filter and change the sand? or is there other filter maintenance (besides the obvious) that I should be doing. My pressure readings are right about 10 psi after backwashing, hence I am not seeing a problem. "Channels" in the sand??

Change? After a baquacil conversion. After discovering someone used floc. When replacing the filter or a broken standpipe or lateral that got damaged by freezing. On a schedule? Never. Fill the filter once and be done with it.

Channeling is possibility. You have water coming in on top and working through the cracks. If there's any goo -- floc, clarifier, sunscreen, whatever -- it can glue it all together. Pressure rises. What do you do? Backwash, and send water the opposite direction where it breaks the layer of sedimentary rock into clods. Then it may not settle back perfectly and then you have crevasses and channels where dirty water can just slip right through unfiltered. Deep cleaning breaks those clods up.