DE backwashing into pool

[Harbisgirl]

Hello,

About a month ago when the temps warmed up, we had a big algae bloom. We shocked the pool and that killed the algae but all green sludge needed to be flushed. We backwashed the pool successfully but noticed that there was more green sludge so we decided to run the filter for another full day and then do another backwash before recharging the filter and starting over fresh for the season. As I was waiting for the backwash, I went over to the pool to get a water sample to check the Ph. Then I heard a pop, and the DE and green sludge started filling the pool from the 3 ports at the bottom of the pool (sorry, obviously I don't know the proper terminology for the equipment LOL) . Yikes. It was a big mess and we ran the filter for another day to recapture it all, but now the backwash just flows straight into the pool. We tried closing the little hatch on the bottom of the 2 skimmers and did another backwash, this time I saw lots of dirty water leaving the filter..but it pumped out through the waterfall.

As a side note, our backwash doesn't come out a separate outtake hose, it is plumbed to go somewhere. I have no idea where...we're on septic and I doubt they'd plumb it to dump DE into the septic tank, we've never seen any water coming out anywhere after backwashes, so we have no idea where it goes - we've had pool guys come out before and they are at a loss as well. There is a little sight glass on the pipe so we can see the water coming out of the filter, so we can see when it is dirty and when it starts to run clean.


Why is our DE pumping into the pool - does this indicate a clog or a break somewhere? If not, is this something that we can fix ourselves?

 

[gwegan]

A overall picture of your equipment pad may be helpful.

With that we can figure out if something is wrong or if something is broken.

 

[jblizzle]

Welcome to TFP!!!

You should NEVER run the water through a DE filter with no DE in it, which is what it sounds like you did. Guessing that the algae clogged up the grids due to the lack of algae and that maybe the pop you heard was something breaking in the filter. That really should not be possible, but it is the only explanation I can think of that would result in DE and algae all flowing back to the pool.

What you also need to remember is that a filter will not clear up a green pool. Algae is a chemistry problem not a filter problem.

{Sorry there was a 2 hour delay between when I started this message and when I could send it}

 

[Harbisgirl]

Thank you, gwegan. Not sure what would be helpful or not so I just took a bunch of pics of everything. Its really hard to maneuver in there so its hard to get a good angle to take pics. Also keep in mind that we did not design and build this, we inherited it from the previous owner

jblizzle, I had no idea that it was bad to run the filter with no DE - why not? We took the filter out and inspected everything, nothing appears broken.

 

[proavia]

Just a guess, but that kind of looks like a DE separation tank on the right side of the second to last pic. My -VERY LIMITED - understanding is it separates the DE out during a backwash. The backwash water - sans DE then returns to the pool. Maybe the containment bag within that tank which separates out the DE failed??

Here's a link to one type of DE separation tank:
Pentair D.E. Separation Tank - Stainless Steel

 

[jblizzle]

That looks like a pretty good guess there Gene

 

[proavia]

That looks like a pretty good guess there Gene

Thanks Jason...... pure luck and a little :google: -ing.