Problem with backwashing filter

[jnorris]

Hi,

I've posted on here a couple of times, and you people have helped me (new pool owner) so much, so here's the next question:

My PB came out last Tuesday (5 days ago) to show me how to operate the equipment, test the water, etc. We backwashed the filter, and it was pretty dirty. Normal pressure after backwashing was about 12, and before we backwashed, it was close to 30. Lots of orange dirt came out, but we had been cleaning the pool for several days before that, and half our yard is the same dirt now (right after construction), so I'm not really surprised. However, I was looking at the pressure on the filter yesterday (4 days after BW) and it was back up to 25. We have no trees in the back yard. Have barely had a speck of dirt get in the pool, and have been swimming a couple of times. Does it make sense that the filter would be that dirty that soon? Also, when I was backwashing, I noticed the little viewing bubble (don't know real name) didn't show any dirt this time (first time it showed all the orange dirt that was coming out.

Do you guys think I have a problem? We haven't paid the PB all of his money yet (still chasing a possible leak) so I have some leverage now.

Judy

[Poconos]

Judy,
Don't know what kind of filter you have...must be sand or DE since you backwash. The orange/yellow stuff is pollen. I also have no trees close to the pool....about 150' but I love in the sticks and there are trees all over. Pollen could easily plug a filter and especially after 4 days I'm not surprised. The viewing thinggy is a sight glass on the waste port.
Al

[jnorris]

Yes, it is a sand filter (sorry!).

We backwashed yesterday, and when I checked it this afternoon, it was back up to 20. Surely I'm not supposed to have to backwash every few days? Could there be another reason the pressure would get high, other than something gunking up the filter? If the water is having to go uphill to return to the pool, would that make the pressure get higher? But then again, if it is 12 after I backwash, and it is 20 the next day, then something must be gunking it up, right?

Judy

[duraleigh]

Hi, Judy.

But then again, if it is 12 after I backwash, and it is 20 the next day, then something must be gunking it up, right?

Yep, almost couldn't be anything else. The water comes out fairly dirty when your backwash, doesn't it?

If so, your filter is simply doing it's job. It'll settle down and when your pool is clean, you'll backwash much less frequently.

[eiffiex3]

I had to backwash my filter 5 times in less than 24 hours the day we opened our pool. I live in the country in Michigan.......no big trees but surrounded by fields. We opened it on Friday afternoon and the pressure kept climbing sooo fast, so I backwashed it every time it got too high. It was quite green as we had a very warm April but now a very cold May. It even frosted last night. It is still quite cloudy, but I will work on that this week. I haven't even tried to balance the chemicals yet......just wanted to get the dirt off the bottom and kill some algae so I could actually see to the bottom of the pool.

[jnorris]

Hi, Judy.



Yep, almost couldn't be anything else. The water comes out fairly dirty when your backwash, doesn't it?

Actually, when I backwashed a couple of days ago, the water didn't look dirty. The first time we did all this brown water came out, so I could understand that. But this last time I watched the sight glass and the water was always clear. My pool water has been clear and blue since we started. We don't have trees around it, and we haven't done much swimming. We do have a heater, and have used it a couple of times. My FC reading is a little low (2ppm) for the amount of CYA I have in there (40), so I'm wondering if there could be algae growning that I'm not seeing? Anyway, I'm going to start using chlorine and take the sticks out of the feeder so I don't add any more CYA, bump the FC level up to 3 - 6 ppm, and call the PB to come check the filter.

Thanks for all the great advice!
Judy

[mshumack]

If this is a "new" gunite/plaster pool you may have a problem with plaster dust coating the filter.

I have a DE filter so I don't know if this applies to sand too ... but when I first opened my new pool I had a similar experience where I had to backwash often. The first backwash dumped a lot of dirty water. After that, the next time I'd backwash the water would flow out clear and return the pressure back to normal for only a few days before I needed to backwashed again. After a coupkle of weeks of this disassembled the filter and found the filter grids covered with plaster dust. Teh backwashing was not removing this dust (paste). I was able to wash the palster off the grids with a garden hose. I never had that problem again after that.

[jnorris]

If this is a "new" gunite/plaster pool you may have a problem with plaster dust coating the filter.

It's a vinyl pool. My husband now says the water coming into the pool from the returns and jets has decreased since the pressure has gone up. After we backwashed the other day, we had good pressure and could have the returns, the jets at the steps, the jets in the swim-out, and the deck jets all running with lots of bubbles. Now there is hardly any ripple.

PB is coming out tonight to check.

Judy