HELP! First filter breakdown and it's full of pieces of what looks like "cement"???

[lkafrazier]

Our pool initially opened less than a year ago and the pressure was up, so we decided to go ahead and have the annual filter breakdown cleaning done.

I'm fairly new to this pool game, but from what I've been researching, I'm going to jump out on a limb as say that it's called DE bridging?? If so, can anyone explain to me in layman's terms what that means, why it's happening and how to stop it?

I have pics, but since this is my first post and I'm a new subscriber, I can't post them yet, but will.


Many, many thanks!
LK

[waste]

Welcome to the Forum!

It's probably DE and is easily removed.

Give this (http://www.poolforum.com/pf2/showthread.php?9189-cleaning-a-DE-filter) thread a read and, if you have questions, I'll help you tomorrow :)

Do you know what brand and model the filter is?

[lkafrazier]

Thank you for the info and I agree it's likely DE that has hardened. My question is why? Too much DE being put in ya think? The filter is a Pentair FNS Plus, DE filter

Thanks again!!

[waterbear]

bridging happens when too much DE is in the filter and it fills the spaces between the grids. This happens when the filter is backwashed and recharged since it s impossible to know exactly how much DE was removed in the backwash it becomes a hit and miss on how much DE to add. This can and will results in either an undercharged filter which leads to clogged grids (which then need to be soaked and cleaned) or an overcharged filter and DE bridging (which you have seen first hand.
Also, when you think about the water flow during a backwash you are forcing dirty water BACKWARDS through the grids and this can also cause the grids to clog.
I am of the camp that DE filters should not really be backwashed but should be broken down for cleanings for the above reasons.