SLAMing for 5 days, but still can't even see the bottom

[bonesmtb2]

I have been following the methods outlined on here for the past 8 years with my pool. However, this year has been a challenge so far.
We got a puppy at the end of last season, and he proceeded to completely destroy the cover over the winter/spring. So, there is probably a ton of organic debris in the bottom of the pool. It proceeded to get very green this spring since there was no cover to block light etc.

I forgot to adjust the pH before starting to raise the FC to shock level on Saturday 5/16.
The water changed color from green to not very green in a matter of 3 days, but the cloudiness has not changed much. I have added some DE to my sand filter in the hopes that this would speed things up.
I have been vacuuming at least once per day, but it is hard to tell how effective I am being, since I can't even see the bottom. I am just trying to generally get the whole bottom of the pool. I have also brushed the sides about 3 times. It seems like the sides might be stained green....hopefully that goes away.

The thing that is confusing, is that my FC isn't dropping much overnight. I raised to a shock level of 16 last night, and it is the same this morning.

Also, here are my other measurements as of this morning:
TA = 30
CYA = 35
CH=20

Any help would be much appreciated. Really hoping the answer is not draining the pool, since when I replaced the liner a few years back it cost about $600 to get it refilled.
Attached are two pictures from this morning. Let me know if I can provide any more info that would help.

 

[ajw22]

Brushing 3X in six days is not enough. Brush two to three times a day. Algae has a biofilm that protects it and brushing breakers the biofilm allowing the chlorine to attack it.

You remove any stairs or ladders where algae can hide?

What is your clean filter pressure and current PSI? When did you last clean your filter?

 

[bonesmtb2]

Gotcha, I will step up the brushing. I am also working from home right now with two little kids, so finding the time is a bit hard.
I have been backwashing the filter pretty much daily. It is usually about 9 psi clean, and has only gotten up to 11psi or so.

Also, it is worth it to let the FC drift down to adjust pH? Or just keep shocking for now and adjust pH later?

 

[Razorhog]

What kind of test kit are you using?

 

[mknauss]

Also, it is worth it to let the FC drift down to adjust pH? Or just keep shocking for now and adjust pH later?

Yes it is. Get the FC down to 10 ppm and test pH and TA. Adjust as necessary.

 

[ajw22]

Backwash when filter pressure rises by 25%. Your filter is doing it’s job, just slowly.

 

[bonesmtb2]

I am using the recommended FAS-DPD test kit. I will brush this morning, then let it drift down to adjust pH and TA, then hopefully get back up to shock level for overnight.
I am just impatient with the sand filter, but I know it is slowly working....

 

[mknauss]

You only need to adjust pH. TA test is used in Poolmath to determine how acid to use to adjust pH.

 

[bonesmtb2]

How long after adding washing soda or muriatic acid do you need to wait to take a new pH measurement? I would think it would be pretty quick.

 

[mknauss]

30 minutes with the pump running. Brushing the pool really well helps too.

 

[IceShadow]

You could also try opening the sand filter and doing a deep clean of it. That might get a bunch of gunk out that backwashing won't remove and help the process along.

 

[bonesmtb2]

Awesome, thanks everyone! Should have the pH straightened out today, then back to full SLAM. I have been brushing 2-3X per day. Starting to see slow improvements I think, just impatient.

 

[Mdragger88]

You should also assume cya as 40 & slam @ 16 per FC/CYA Levels
Always round up if you’re in between -failure to do so can make SLAM Process drag on

 

[ethany]

Sorry I’m not trying to hijack this thread but why is it so important to adjust the ph before slamming? Does having a high/ low ph affect the slamming process?

 

[mknauss]

Primary reason is that you cannot test pH when the FC is above 10 ppm, which is normal during a SLAM. Secondarily, chlorine is more effective at lower pH, though that is muted with CYA in the water.

 

[ajw22]

Sorry I’m not trying to hijack this thread but why is it so important to adjust the ph before slamming? Does having a high/ low ph affect the slamming process?

Large amounts of chlorine are more effective at low pH.

Does_Pool_pH_have_an_Effect_on_the_Chlorine’s_Ability_to_Sanitize_Water?

 

[bonesmtb2]

So pH is 7.0-7.2 now.
FC was 10.5 this morning, so will add chlorine to get back up to 16 and brush. Then I guess it is just a SLAM waiting game. Attached are some pics from this morning. Can only see about halfway down still.
I also backwashed the filter this morning. It was at 12psi, and after backwash was at 8psi. Added some DE to get it up to about 9psi or so.

 

[IceShadow]

Have you tried a deep clean of the sand filter? Sometimes that makes the clearing go a lot faster, with all the crud that backwashing doesn’t get out of the filter.

 

[bonesmtb2]

I have not yet. I will see what that entails, and see if I can find time to do that.

 

[IceShadow]

Deep Cleaning a Sand Filter

This post will walk you through the anatomy of a sand filter, and then provide a video at the end for how to deep clean your sand filter. The filter used in the photos and videos is a Hayward S180T top mount sand filter. The images are of a similar filter. Obviously not all filters are...

www.troublefreepool.com

I did it and got about 10 lbs of pine needles out of my filter last year. Was pretty nuts. They wouldn’t backwash out due to the shape. Lots of other crud too. Since then my pool has been crystal clear.