Orange/Brown Dust on Bottom of Pool, Passing OCLT

[Surf Hawk]

Last week I had to vacuum up some orange/brown stuff on the bottom of the pool just a few days after my normal weekend vacuum. It was only on the bottom and equally in shade and sun. I also have medium size debris suspended in the water even after the pump has been running all day and the water doesn't have the clear pop it usually has after my weekend routine. I thought is was construction dust from the house next door. My filter pressure went up crazy after vacuuming and I had to backflush earlier than expected. The construction has stopped and I still had to brush this stuff off the bottom of pool yesterday and my filter pressure went up another few PSI. I've ran two OCLT test and passed both of them with no FC usage (actually my FC was a bit higher than the night before, confused on that).

I am embarrassed to admit I have really high CYA from the previous owner's pucks so have to keep my FC high until I drain. We are in a Stage 2 drought and pool drain/refill is not permitted now. I'm hoping to collect rainwater this winter to lower my CYA and CH, I am only using bleach now so no new CYA is going in.

I have been keeping my FC at 15 the last few months without any problems.

PH 7.5
FC 16.5
CC 0.5
TA 120
CH 1,000
CYA 200
Temp 90

If it isn't algae, is my filter just doing a poor job and needs to be manually cleaned?

 

[Richard320]

Look at the patio furniture and the windowsills. If they have the same dust, it's from next door.

If you've never cleaned your filter manually, maybe now would be a good time. I've noticed that the cellulose gets gooey if it goes too long and doesn't backwash out as well as it should. They say it's biodegradable, so maybe it's biodegrading!

After it;'s back together and recharged with cellulose, concentrate on the circulation. If there's no main drain action, aim a return down there so whatever is in the water gets stirred up so it can get sucked into the skimmer.

 

[Surf Hawk]

Well no dust anywhere else really so that theory wasn't a good one

I haven't cleaned the filter manually so was going to this weekend. However after swimming in it this afternoon with goggles I decided to clean it out manually. However I made a really big mistake. After I put it back together there was a leak where the two halves clamp together, I didn't discover this until after I put the cellulose fiber back in via the skimmer. So I stopped it and took it apart to clean the seal. However I forgot to put the valve in the "close" position and water started to drain out of the filter and back into the pool. That led to cellulose fiber draining into my pool. So now my pool is really cloudy.

I'm hoping the circulation will eventually scoop up all that cellulose fiber and put it back in the filter. I have a main drain and adjusted my skimmer float so it is sucking from there mostly.

Thanks for the help.

 

[Surf Hawk]

I am getting this weird thing where I am measuring higher FC levels in the morning than the evening in my OCLT tests.

Monday 5pm: 16.0 - Added 1 Gallon 12.5% and kept pump on
Monday 8pm: 21.5 - turned pump off (5.5ppm rise)

Tuesday 7am: 24.0 (3.5ppm rise?)
Tuesday 8pm: 21.5

Wednesday am - could not test
Wednesday 8pm: 18.0 - Added 1 Gallon 12.5% and kept pump on
Wednesday 10pm: 22.5 - turned pump off

Thursday 8am: 25.5 (3.0ppm rise?)

My chlorine demand in the day is higher than usual, I think I have algae that is dying and ending up the bottom because of my high CYA/FC I am never seeing it alive. My CYA would make my shock levels 80ppm. My city says I can drain/refill 33% but I need to do about 80%. 80% is going to cost about $350 in water. I should of drained last winter before the city raised rates with our drought.

 

[Casey]

I don't know why you are getting the higher FC levels in the morning.

 

[Surf Hawk]

Thanks for the reply. I have decided to be more accurate with my testing, got a 5ml syringe so I can measure out my 10ml for the FAS-DPD test. I also think I may have been putting in less powder, as I was doing level scoops in my test tonight all of the powder dissolved and the solution was clear. I had to add a little more until some was still un-dissolved and it was pink.

Tonight at 8pm I got 25.5 FC again, just the same as 8am. I'll chalk it up to user error with my above issues. Hoping tomorrow morning I don't get a higher reading than tonight.

Pool was looking pretty clear this evening, I think all the cellulose fiber that got sucked back into the pool found it's way back to the filter.

 

[Surf Hawk]

Dang I got a 2.5ppm rise this morning at 7am compared to last night at 8pm. I don't know what I'm doing wrong. I don't have an swg and I had the pump off and the solar cover on that whole time. Does chlorine rise to the top when a pool is covered and no circulation?

Also, here is a photo of my DE filter grids when I cleaned them, a bit of green algae on them, as was the case when I manually cleaned it 6 months ago.

 

[Surf Hawk]

Retested CYA and for the first time used the 4x dilution method. Got 180 CYA using 4x method and 160 CYA using 2x method. Still really high but better than the 200 I had sometime ago.

 

[Casey]

Are you rinsing your tubes before and after each test?

 

[Surf Hawk]

I have been bad in the past about rinsing with pool water instead of fresh water, but for the last few tests have made sure to rinse with fresh water.

 

[PAGirl]

The pump should be on for at least 30 minutes to circulate before testing.

 

[Surf Hawk]

Thanks, I am now doing the morning test now after the pump running. Still not getting consistent results between night and day but if anything I'm showing my FC in the am than the PM so I'll assume I pass OCLT.

My latest theory is that my DE filter is doing a poor job, even after a backwash. When I swim in the pool with goggles, it just isn't as clear as it used to be and I see things suspended in the pool, little bits of leaves and other "floaters." Now that I think about it, when I pulled the grids out of the filter, one of the grids may have had a little tear. Could a little tear keep the filter let enough stuff bypass filtration and give me particles floating around?

The orange stuff on the bottom is gone but I definitely have more stuff on the bottom when I brush or vacuum than I usually do.

 

[Abigail K]

Thanks, I am now doing the morning test now after the pump running. Still not getting consistent results between night and day but if anything I'm showing my FC in the am than the PM so I'll assume I pass OCLT.

If inconsistent results between night and day means you're losing FC, that means OCLT fails.

 

[Surf Hawk]

Actually my morning test has never shown less than the evening before, for some reason always more. I am working on finding the mistake in my testing.

 

[Abigail K]

Do you test after adding bleach, or do you assume it is at the level you targeted?