Going to try my newly learned skills on a friends pool.

He lost use of his pump for a week or so and it got bad. It's approx 45,000 gallons. Vinly Liner. He has a SWCG AND a Nature2 system (the installer said his pool was so big it was pusing capacity of the SWCG and said the Nature2 would help). His SWCG is broken right now so he's been using tablets. He has never put anything in his pool besides salt and shock. He has a cartridge filter not sure the brand we have just been talking via email so far. The Nature2 cartridge is old and he was going to replace it but I told him to hold off until I discuss here.

So I'm prety sure his CYA is going to be unmeasurable. Should I test it first or would that just be a waste of 7ml of reagent? Since he has a cart filter, can you add the CYA to the skimmer directly or use the sock method?

He says the water is blue but cloudy. Very fine particles. Does he need to flock it then waste vac it or do you think we can work through that?

I'm supposed to go test the water this evening but I wanted to pre-post and let you smart people know where my head is at on this project before it starts and correct me if I am wrong.

Thanks!
-stephen

Go ahead and run a full set of numbers including CYA. Tell him not to bother with the Nature2 thing. We don't think too highly of those things around here.

Since his pool is cloudy and he will likely have to be cleaning his cartridge frequently as it filter stuff out of the water, best to use the sock method to add CYA.

Forget the flock. Bleach, bleach, bleach and filtration. Oh, and *POP!! Lots of it!

* = Pool owner patience!

OK. His pool isn't very cloudy now and you can see the bottom in the 8' deep end.

FC: 0
pH: 8.0
Alkalinity: 90 ppm
CYA: 0 (unmeasurable)

I told him to go get:
-gallons of bleach to add in the AM and PM to get him some FC
-12 lbs of CYA (3 containers) and go ahead with the sock method (he has 2 skimmers, 1 sock in each skimmer)
-muriatic acid

I told him to try and get the CYA this evening to get that step kick started ASAP as he has a party to throw this weekend.

Did I miss anything to get things started?

OK. With those numbers, using lots of Tri-chlor tabs is not a bad thing...High pH, low CYA..Tabs are acidic and release CYA.

I suspect the reason the builder put in the N2 was because he KNEW he had put in too small an SWCG. Now it's broken, probably due to running flat-out at "flank speed". N2 kills algae, which can lower your chlorine demand...but the cost is far more than the cost of bleach. And, when the cartridge is old, they are useless even by the N2 standards.

If you have Trichlor tabs, use them. But you'll need bleach and acid to adjust FC up and pH down.

Carl

He needs to add some acid -- preferably muriatic acid from Lowes or a hardware store -- and get his pH down. Generally, a reading of "8.0" doesn't mean '8 exactly', but rather '8 or higher', which is NOT OK.

If he really has 44,000 gallons -- that's VERY large for a home pool -- having add 1/2 gallon of acid but NOT at the same time or in the same place as the bleach.

When adding muriatic, wear glasses and gloves, and pour the acid very close to the water. The easiest way is to partially submerge the bottle in the pool before beginning to pour. This also minimizes fumes.

And if he's not already, his pump should be on 24/7 during any chemical addition or clean up process.

Jilted: All the advice you are getting from us all works together. Good luck!

Carl