New to the forum - Trying to get a handle on pool chemistry

[CompostPile]

One question...

How fast does the CYA level drop? The new kit will not arrive until next week so I don't have a way to test if the CYA is dropping. I will continue to monitor the chlorine best I can and try to keep it at 15ppm until the pool is clear.

Jamie

[Watermom]

CYA levels are pretty consistent throughout the season once you add it. You lose a little to splashout and refill but over all, not much.

[CompostPile]

I ran the vacuum to waste last night. I could see a big color difference from where I vacuumed to where it still had junk and could see the color in the clear pump lines change to brown when I was sucking up the junk so it was really bad. I needed to refill about 5" of water after that was done so I also added one bottle of bleach to make sure chlorine levels were plenty high. This morning the water is a nice blue color, but still cloudy. I took a sample in to check CYA levels again and they said its now at 10 probably due to the changing out of so much water. I have some stabilized tables left over. Can I use them to bring the CYA level up some and supplement the bleach for chlorine or will that throw things off. I don't want to undo whats been done so far. Thanks so much for all the help so far.

Jamie

[aylad]

You can absolutely use the tablets to help raise the CYA levels--just keep an eye on your pH and make sure it doesn't get too low--trichlor tabs are acidic and can drive pH downward. It's fine to use the tabs and the bleach at the same time in the pool--after all, it's all chlorine when it gets in the water. Just don't let the bleach and tabs come into direct contact with each other before they're in the pool.

Janet

[CompostPile]

Please ignore the question in the last post. After further investigation, the tablets I have left over are not stabilized. They only contain calcium hypochlorite.

I am guessing that CYA of 10 is really too low and should be increased. Since the good test kit is not supposed to arrive until late next week, and don't want to over do it, should I wait until next week to try and mess with it and just try and keep the chlorine levels above 5 until then?

[Watermom]

Go ahead and add a lb. of stabilizer. A week from now, test your level and see where you are then. It should be somewhere around 35ppm or so if the reading of 10 is correct. (It really isn't possible to differentiate levels that low but you know that is is low, so adding a lb. should be about right.) I estimated your volume to be around 5000 gallons.

[CompostPile]

Had the water tested at the pool store again today to see how the CYA is doing.

FC: 5
TC: 5
CYA: 50
PH: 7.4
TA: 220

The pool is nearly clear, just a little bit of cloudy, but this is the best I have seen it since it was filled.

The pool store person mentioned that the TA level has high and would rust out the metal frame. When I add bleach, the PH rises so I use acid to bring it back down, will this normal use bring the TA into check over time? Or do I need to get this down sooner and start adding acid at regular intervals and then use something to bring the PH back up?

Thanks again for all the help so far... The kids finally will get to use the pool again this afternoon and are extremely happy.

Jamie

[aylad]

Sounds like you're making some progress--just keep the pump running and clean the filter as your pressure indicates until all the dead algae is out of the water. And make sure that your chlorine level never drops below 3 ppm so you don't have to fight that battle again! Your TA level is not high enough to cause concern about rusting. Also, it is normal to have a temporary rise in pH when using bleach, since the pH of bleach is 13! However, as the bleach is "used up", the pH goes back down--so don't adjust your pH just to keep up with the bleach.

You don't list a reading for calcium hardness--if your CH level is high, then dropping the TA can have a clearing effect on the water. Also, if you were to lower your TA down to around 80 or so, you might find that your pH is a lot more stable. However, if the TA of your fill water is 220 or higher, then it'll be a constant fight to keep the TA down due to frequent refilling, and since it's not really causing you problems, it really can be left alone for now. Those things would be the determining factor in whether or not I would lower the TA if it were my pool. If you decide to do so, here is the procedure: http://www.poolforum.com/pf2/showthread.php?t=191

Above all: if the kids are going swimming in a cloudy pool, make sure you keep a good eye on the swimmers, especially in the deep end--cloudy water can make it hard to see somebody who is in trouble!!

Janet