Longest SLAM I’ve ever done.. still cloudy

[Donnie Darko]

Hi all,

I had some problems with keeping my tarp cover on this winter (very windy season) and it basically blew completely off early April. At this point I just removed it, but unfortunately lots if leaves/debris fell in. I scooped out as much as I could, but the pool was already green. I wasn’t really prepared to start everything up so I let the pool sit for about a month and it turned into a swamp.

I started my SLAM 15 days ago and by day 2 all the green was gone and was a thick cloudy white. CYA was initially very low. I raised it to 30. I vacuumed and brushed every 1-2 days and periodically ran the polaris robot vac. I was still picking up debris up until about 3 days ago. Now it’s just dead algae. I probably haven’t done a perfect SLAM, but I have generally kept the chlorine between 10-14ppm. I have ran the filter constantly for the 15 days. I have a sta rite system 3 cartridge filter and clean it whenever the pressure raises more than ~30%.

The water quality has improved, but very slow and I can still just barely see the bottom of shallow end. I lost a vacuum head in the deep end which I don’t think I will be able to recover any time soon.

Lastest readings (TF-100)
FC = 10
CC = ? (I need more reagent)
pH = 7.0
TA = 50
CYA = 30-35

Other pool details-
IG ~35,000 gallons
Vinyl liner
Cartridge filter
Salt water system no longer functioning (so I use BBB now)

Any ideas? My cartridges are old (about 12 years), they are a bit beat up looking, but everytime a clean them the pressure drops to the original starting pressure and flow is good. However, lately the filter will run for days without any noticeable increase in pressure, which makes me think no progress is being made. I usually have a slight increase after vacuuming. Sorry for the long post, any help will be greatly appreciated. Thank you.

 

[jblizzle]

Perhaps the cartridges are going bad and letting the fine debris pass through?

 

[Donnie Darko]

Yeah, might be worth replacing them at this point and see if that helps.

 

[C.Johnson]

A couple things:

The first; do you have a main drain in the bottom of the pool? Isolating suction to that will help clear up the pool faster.

How much is your chlorine falling overnight?

 

[Donnie Darko]

I do have a main drain. I installed new cartridges on Wed and there has been a little improvement, but not much. I just switched to main drain only today after reading your post. Last time I checked my overnight FC loss was less than 1 ppm.

 

[Donldson]

Isolating suction to that will help clear up the pool faster.

Could you elaborate on this comment? If everything is dead and we are at a point of simply filtering then the clearing time is a function of how quickly the filter is catching debris. How is closing off the skimmer going to accomplish this?

 

[duraleigh]

Isolating suction to that will help clear up the pool faster.

That caught my eye, too. +1 what Donldson said

 

[Donnie Darko]

Willing to try anything at this point. I turned my skimmers back on though (too much debris sinking). At this point I will move on to my normal filter runtime and Cl levels. No noticable change in filter pressure since new cartridges were installed. I’ll give it time though. If it doesn’t clear up by the end of the season, I’ll consider converting to a DE filter next year.

 

[Donnie Darko]

These are my latest numbers:

FC- 5.0
CC- 0.5
pH- 7.4
TA- 50
CH- 80
CYA- ~35

Any other ideas? It’s been about 3 1/2 weeks since i opened and I can see down about 4-5 feet (barely). If filter pressure isn’t rising, is it possible that there is nothing left to filter and something else is causing the cloudiness? Or the particles are too small for the cartridge filter...maybe a clarifier? Partial drain?

 

[duraleigh]

A cartridge filter removes all visible particulate if it is not damaged or installed correctly. If there is "nothing left to filter" then your water would be perfectly clear.

If you are getting no psi increase, your filter must be damaged/installed incorrectly for that to occur.

 

[Donnie Darko]

Initially the pressure rise was significant. Starting pressure is 13 psi and I had to clean the cartridges on day 2 (about 17 psi) and again on day 5 (about 17 psi). After each cleaning, the pressure returned to 13 psi. The water clarity improved significantly that first week. Then it took about 2 weeks of consistently running to reach 16 psi. I don’t believe there was much increase the 2nd week. This is when I replaced the cartridges thinking after 12 years they may be less effective at filtering out the finer stuff. New cartridge startup was 13 psi. After 5 days, the gauge reads about 13.5-14 psi (gauge seems to bounce around slightly). I’m pretty confident they are installed correctly. Possibly defective. Maybe I should clean the old ones and go back to them and see if I can exchange the new ones?

 

[duraleigh]

What does your water look like? Are you seeing improvement? How many hours daily are you running the pump?

 

[Donnie Darko]

I pulled the cartridges out after my last post just to inspect them and they had collected a decent amount of junk even though the pressure only increased about 0.5 psi. I cleaned them since they were out. No real pressure increase since cleaned, but water is improving slightly. I’ve vacuumed to waste a few times, but not much debris sinks from what I can see. I can see the bottom of shallow end pretty clearly, deep end I can see the brush head going down about 6 ft. Brush almost daily and keep my FC between 5-6. I run the pump about 12 hrs now. Thanks for your help.

 

[C.Johnson]

Could you elaborate on this comment? If everything is dead and we are at a point of simply filtering then the clearing time is a function of how quickly the filter is catching debris. How is closing off the skimmer going to accomplish this?

That caught my eye, too. +1 what Donldson said

Sorry for the delay. What I was taught and my experience is that pulling water from the bottom of the pool, or 70/30 MD/Skimmers clears the pool up faster than leaving everything open or pooling entirely from the skimmer.

How's the chlorine demand now?

 

[Teald024]

I run the pump about 12 hrs now.

You should consider going back to running the filter 24/7. At 12 hours a day, you are only filtering half of what you could be filtering each day.
What type of pump do you have (1 speed, 2 speed, variable speed)?

 

[Donnie Darko]

How's the chlorine demand now?

Chlorine demand seems normal, 1-2ppm per day depending on sun. I plan on raising the CYA to 40, but was waiting for clear water just in case I need to bring it back up to SLAM level. However, CC’s are near zero and everything looks good besides clarity. Improvement is extremely slow, but noticable. The pool was a thick green swamp when I started so I guess it could just take this long to filter out. I will do a better job of keeping the cover in place next winter. I never thought it would be this difficult to get clean.

You should consider going back to running the filter 24/7. At 12 hours a day, you are only filtering half of what you could be filtering each day.
What type of pump do you have (1 speed, 2 speed, variable speed)?

I will. I cut the run time down out of concern that there wasn’t any improvement and was a waste. The pump is a single speed 1 3/4 HP, so it’s not doing my electric bill any favors.

 

[Donnie Darko]

Just an update:

Day 37 since opening and I can now see the main drain (8 ft down)! Just barely can make it out. I think by next weekend it might be crystal clear. Back to running the pump 24 hrs and started using filter socks last week, which are collecting a considerable amount of gunk. No much rise in filter pressure, but maybe the debris it’s collecting isn’t heavy enough to cause a noticeable increase? Anyway, progress is being made so I’ll just keep at it. Thanks again for everyone’s help!

 

[C.Johnson]

Appreciate the update, glad you are going the right direction!