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purplegirl
08-06-2011, 09:07 AM
I have an intex 5000 gallon pool with a 1hp hayward 150lb sand filter. The pool is a touch of green and slightly cloudy.
FC - 6ppm but just added half gallon bleach. I wanted to raise FC in the hopes of clearing the pool, plus I'm having a large bather load later in the day.
CC - 0
CYA - 50
TA - 80
PH - 8.0

I'm assuming the pool is cloudy and green because of the high PH.
I don't want to use muriatic acid. I have citric acid in the house, but because the FC is so high I'm not sure the citric acid will take. I also don't know how much to add.
I can purchase PH down at the store, but wanted to ask here first about the citric acid.

waterbear
08-06-2011, 10:35 AM
No!!!!!
Citric acid is what is known chemically as a 'weak' acid. Muriatic acid (and the Sulfuric acid that forms when dry acid dissolves in water) are what are known chemcally as 'strong' acids. This has to do with their dissociation constants.

Why don't you want to use muriatic acid? It really is the best thing to use and is no more dangerous than many other household chemicals that are probably already in your house.

Your pool is cloudy and green because you did not keep up your FC levels and you got an algae bloom.

aylad
08-06-2011, 04:28 PM
To clear up the pool,often as possible. YOu want to maintain this until the pool clears up, running the pump 24/7 and cleaning the filter as your pressure indicates. Go ahead and adjust your pH first, though, because with the chlorine at "shock" level, your pH testing may read falsely high.

chem geek
08-06-2011, 04:36 PM
If you were to use citric acid, then the chlorine would oxidize it and produce copious amounts of trihalomethanes (THMs), especially chloroform. You most certainly do NOT want to use citric acid for lowering the pH. If you were to get half-strength (15%-16%) Muriatic Acid, then it would fume a lot less, but if you don't want to use that either, then use dry acid (sodium bisulfate). While not ideal, it is at least a strong acid you can use.