50 Thousand Gallons of Cloudy Mess

[korinian]

I have a 50k gallon vinyl pool with a looploc cover. I opened it, two weeks ago, to a mess of algae... which is par for the course. I've used the BBB method for a number of years and haven't really had an issue with it until this year.

The initial numbers were:
FC - 0
TC - 5
PH - 8.4
TA - 30
CYA - 30

I bought 60 bottles of GV Bleach, Muriatic Acid, Baking Soda, etc.. and started the whole opening process.

After 1 week my numbers:
FC - 16
TC - 0
PH - 7.2
TA - 90
CYA - 50

The algae was nuked pretty quick. But the water is still really cloudy. My chlorine levels drop like they are supposed to overnight.

Yesterday makes 2 weeks I've been keeping my cholorine in the 12 to 16 range. I'm scrubbing walls, and backwashing once my pressure dictates it. Again, the algae is dead, but the water is still really cloudy.

Am I missing something? Do I need to get my FC level higher for a longer period of time? The sand in the filter is 2 years old... do I need to add DE? Temps in Oklahoma have been in the 90's for the last week.... Or am I just being impatient. Any ideas would be awsome! Thanks.

Dave

 

[JasonLion]

You should be seeing a visible improvement in the water each day. If you are not, then something is probably wrong with your filter.

What kind of filter do you have, and how has the filter pressure been behaving?

 

[Butterfly]

You can try adding some DE and stick a round to keep an eye on the pressure:

pool-school/add_de_to_a_sand_filter

 

[Butterfly]

You might want to also try a deep cleaning on the filter:

my-sand-is-channeled-how-to-fix-it-t7626.html

BTW, what size sand filter is it?

 

[korinian]

My pump is a Hayward. Not sure of the model, but it's 1.5 hp. Starting pressure is about 11 the filter runs for a couple of days and it goes up to about 25 to 30. I backwash, and it goes back to about 10 or 11. It all seems really normal, just like any other year. The sand filter is 300lbs. I replaced the fingers 2 years ago and changed the sand out even though it wasn't that bad.

 

[Butterfly]

You should backwash when the pressure rises about 20 to 25% above starting/clean filter psi.

 

[duraleigh]

That pool will always take a VERY long time to clear. The filter is too small for the pump and w-a-ay too small for the pool.

Short of replacing the filter for a MUCH bigger one, about all you can do is keep doing what you are doing but holding your chlorine up high at shock value the entire time.

I would suggest you backwash @ 15 psi. It may seem a hassle but it is far more efficient and will actually speed up the process a bit.

 

[rdhetrick]

My chlorine levels drop like they are supposed to overnight.

Are you saying your chlorine DOES drop overnight? It's not supposed to......

 

[korinian]

Yes, it drops about 1 ppm overnight. That's the way it's always been once the pool is up and running. I always figured that was just the normal "decay rate" of cholorine over time.