Cloudy water won't clear

[Ctheronj]

TLDR: SLAMming pool for past 5 or 6 days, colorless but cloudy/milky, not sure about filter effectiveness. The instructions for our filter talk about rinsing the filter with a garden hose and say nothing about DE, but the filter is a "DE" model. Should I try adding some DE?

Long Version:

I opened our pool for the first time ever (new house) about two weeks ago. Did a ton of reading on TFP first, ordered a test kit, etc. Took cover off, a lot of pine needles and other debris at the bottom of the pool, water sort of brownish green but fairly clear (colored but not cloudy), removed as much debris as I could with a leaf rake. We are talking hundreds of scoopfulls. Was unable to get the vacuum working properly (poor suction) so just did as much as possible with the rake.
Topped off the water (to bring it from below the return outlet to mid skimmer height). We have unusually pure city water here.

tested basic parameters before adding chemicals:
pH 7.4
alkalinity 40ppm
calcium hardness 60 ppm
CYA <30 (the lower limit of my test kit)

Placed a cotton sock with 2 lbs of CYA into the skimmer (should raise CYA by 20 ppm according to poolmath, have not retested) and have been adding bleach to keep the FC at least 12-14. (I test before adding chlorine, to try to see what the chlorine level is at its lowest).

I have been maintaining these SLAM numbers for about six days. The past few days have only had to add bleach once per day in the evening. the water is totally colorless now, but has gotten very cloudy to the point where it is hard to see anything on the bottom about four feet down. CC is 0.5. I have not done an overnight loss test because the water is nowhere near clear. Looking at the water, there are visible white particles in suspension. They look more organic than crystalline. I have rinsed out the filter several times (there is no facility to backwash it, you must drain all of the water about fifty gallons I would guess, then rinse it off with a garden hose), and the PSI of the filter starts around 12 but within a few minutes has already climbed to 15 or so. It gets up to 20 if left a day or more and does not move much water at that point.

Do I need to add DE to this filter (Clearwater II DE)? If so, how much. Everything about this filter on the manufacturers website and the paperwork left with the house says to rinse the filter but says nothing about adding DE. The label on the side of the filter says it is either 12 or 18 square feet, and does not say which anywhere that I can tell, that would suggest using about 1.5 to 2.25 lbs of DE, do I just weigh it out, mix it in a slurry with some pool water and pour in the skimmer after cleaning the filter? Any down side to this if it is actually not meant to have DE in it? The filter certainly does not seem to be performing very well currently.

Thanks in advance

CJ

 

[max2k]

TLDR: SLAMming pool for past 5 or 6 days, colorless but cloudy/milky, not sure about filter effectiveness. The instructions for our filter talk about rinsing the filter with a garden hose and say nothing about DE, but the filter is a "DE" model. Should I try adding some DE?

Long Version:

I opened our pool for the first time ever (new house) about two weeks ago. Did a ton of reading on TFP first, ordered a test kit, etc. Took cover off, a lot of pine needles and other debris at the bottom of the pool, water sort of brownish green but fairly clear (colored but not cloudy), removed as much debris as I could with a leaf rake. We are talking hundreds of scoopfulls. Was unable to get the vacuum working properly (poor suction) so just did as much as possible with the rake.
Topped off the water (to bring it from below the return outlet to mid skimmer height). We have unusually pure city water here.

tested basic parameters before adding chemicals:
pH 7.4
alkalinity 40ppm
calcium hardness 60 ppm
CYA <30 (the lower limit of my test kit)

Placed a cotton sock with 2 lbs of CYA into the skimmer (should raise CYA by 20 ppm according to poolmath, have not retested) and have been adding bleach to keep the FC at least 12-14. (I test before adding chlorine, to try to see what the chlorine level is at its lowest).

I have been maintaining these SLAM numbers for about six days. The past few days have only had to add bleach once per day in the evening. the water is totally colorless now, but has gotten very cloudy to the point where it is hard to see anything on the bottom about four feet down. CC is 0.5. I have not done an overnight loss test because the water is nowhere near clear. Looking at the water, there are visible white particles in suspension. They look more organic than crystalline. I have rinsed out the filter several times (there is no facility to backwash it, you must drain all of the water about fifty gallons I would guess, then rinse it off with a garden hose), and the PSI of the filter starts around 12 but within a few minutes has already climbed to 15 or so. It gets up to 20 if left a day or more and does not move much water at that point.

Do I need to add DE to this filter (Clearwater II DE)? If so, how much. Everything about this filter on the manufacturers website and the paperwork left with the house says to rinse the filter but says nothing about adding DE. The label on the side of the filter says it is either 12 or 18 square feet, and does not say which anywhere that I can tell, that would suggest using about 1.5 to 2.25 lbs of DE, do I just weigh it out, mix it in a slurry with some pool water and pour in the skimmer after cleaning the filter? Any down side to this if it is actually not meant to have DE in it? The filter certainly does not seem to be performing very well currently.

Thanks in advance

CJ

Welcome!

It would be great if you could test and post your current CYA level.

DE filter type is one of the best in terms of filtration but they require extra care. All DE filters require DE otherwise they don't filter much. If you were back washing the filter (not actually cleaning grids inside) then you problem is most likely due to not having any DE left in there. Please ensure the filter is full of water before adding DE by opening air bleeding valve somewhere on top of the filter. This will ensure the internal grids are fully covered with water. DE is added as you described through the skimmer with pump running.

 

[needsajet]

That was weird. I found 3 versions of your manual and all three said to refer to the startup instructions after cleaning, and startup instructions were not in any of the versions of the manual! Writing of manual outsourced, haha.

Anyhow, I found this in the FAQ section

D.E. is added through the skimmer with the pump running. Each filter has a different requirement of D.E. At initial start up or after a thorough cleaning, the filter will need to be pre-coated with D.E. The filter label will state the amount of D.E. required. Start the pump and once the pump is fully primed, slowly add the D.E. into the skimmer. The pump will draw in the D.E. and send it into the filter, where it coats the grids. Once the require amount of D.E. is added, take a reading of the filter’s pressure gauge. This is the clean starting pressure of the filter. When the pressure rises 8-10 PSI above the starting pressure, it is time to backwash or clean the filter. After the filter is backwashed or thoroughly cleaned, by taking it apart and hosing it out, you will need to pre-coat the filter again with the entire amount of D.E. stated on the filter label.

- - - Updated - - -

And this was the best of the three versions of the manual on the Waterway Plastics website: http://www.waterwayplastics.com/manuals/810-0067.0109.pdf

 

[Ctheronj]

Thanks for the help! I think you both have convinced me to go ahead and add DE to the filter, which I will do later this morning. I will post fresh numbers when I get a chance as well. I had not rechecked the cya level as I read somewhere on here to wait a while after adding before testing, I was also worried about the baseline cloudiness confounding the results (it is a clarity based test in my kit).

 

[Ctheronj]

CYA 50
FC 20
CC 0.5

I added DE to the filter this AM. Within 2 or 3 hours the PSI had risen from 15 to 20 and throughput of the pump was very minimal so I performed a poor mans backwash (by opening the drain valve at the bottom of the filter and allowing water to course backwards out of the pool and through the filter in reverse, it was very chalky looking) which seemed to restore the original PSI. Then added more DE (should I add the original amount or a lesser amount after doing this?). So I think that we are making some headway, though the idea of cleaning or backwashing the filter five or six times per day seems like a lot of work.

 

[max2k]

CYA 50
FC 20
CC 0.5

I added DE to the filter this AM. Within 2 or 3 hours the PSI had risen from 15 to 20 and throughput of the pump was very minimal so I performed a poor mans backwash (by opening the drain valve at the bottom of the filter and allowing water to course backwards out of the pool and through the filter in reverse, it was very chalky looking) which seemed to restore the original PSI. Then added more DE (should I add the original amount or a lesser amount after doing this?). So I think that we are making some headway, though the idea of cleaning or backwashing the filter five or six times per day seems like a lot of work.

DE makes back wash water chalky, that's normal. If you kept rinsing it until back wash water became clear then 80% of DE was washed out. You'd need to recharge your DE again. It seems it gets clogged with something in your water quickly, I back wash mine once every couple months at most so I expect yours to become this way after it's done clearing up your water.

Can you post picture of your pool stairs or any other part providing gradual depth view of the water in daylight?

 

[Ctheronj]

I did four backwashes and one bona fide filter cleaning in the past 24 hours and the water is looking remarkably clearer this morning (eight hours overnight was still enough to completely reduce the flow to a standstill despite only a 25 per cent increase in PSI).

I finally heard back from the manufacturer about adding DE... they did confirm that it needs to be added, although did not supply any instructions.

thank you all for the help. Hoping to be swimming by this weekend!

 

[max2k]

I did four backwashes and one bona fide filter cleaning in the past 24 hours and the water is looking remarkably clearer this morning (eight hours overnight was still enough to completely reduce the flow to a standstill despite only a 25 per cent increase in PSI).

I finally heard back from the manufacturer about adding DE... they did confirm that it needs to be added, although did not supply any instructions.

thank you all for the help. Hoping to be swimming by this weekend!

this is DE filter, it won't filter much without DE in it.

When was the last time you opened the filter and examined/cleaned the internals? Please read DE section here if you haven't already, it also contains link to the post with more details on the process.

When eventually water becomes crystal clear the filter should not be clogging up that quickly. Please maintain correct level of FC at all times. If dead algae falls to the bottom vacuuming to waste of the bottom would also make this process faster.