Year 2 Trouble, what do I do with this chemistry???

[Anna1786]

I was able to get my 20,000 gal pool clear using the method last year, and it was awesome. This time around I'm pretty sure I messed things up. I had no CYA to begin with so I shocked the pool with sodium dichlor about 10 lbs of it to raise cya. I started the process on 05/29 and the pool is still super murky and my numbers are way off, please help!!
Ph. ... Less than 7
TA..... 10 yes ten
Cya... 100 yes one hundred
Calcium hardness.... 70
FC.... 6

I don't know which I need to fix first to get the water balance right. Pool is definitely still pretty green.

 

[JVTrain]

You've got a few issues to tackle. In order to help you better, please add your location to your profile. Did you just open the pool after having it closed?

First thing to address is the pH. However, you have a high CYA issue as well. I'd recommend draining close to 50% of your pool volume and refilling. Likely, your fill water has a higher TA than 10 and that will save you some money on chemicals to bring up the TA and pH. Test your water after refilling for CYA, pH and TA and we'll go from there.

Also, if you're filling with city water, notify your city department that handles water billing and let them know you're adding 10K gallons to your pool. Most cities will waive sewer fees if you state the water is going in the pool... unless you're draining into the city sewer.

 

[DanielP]

What he said, but while filling the pool, you might make the hose squirt a hard jet into the pool so it aerates the water to help bring ph up while filling. It will take longer to fill though.

 

[Richard320]

I sure hope you don't live in California, because a partial drain to lose that high CYA is step one.

And stop with the dichlor! That stuff is really acidic, as you now can see for yourself. It could be etching the metal inside your heater, even. And it adds CYA at an alarming rate as well.

What test kit are you using? And do you have a lot of FAS-DPD and CYA reagents left? It might be prudent to order some refills now.

Step One: Partial drain. You have a sand filter, so you almost certainly have a multiport valve, so you have the option of connecting the vacuum and setting the multiport to waste and - clever name, this - vacuum to waste. Any sludge and debris on the floor will be sucked up and shot out the waste pipe and out of your life along with the overloaded CYA water.

Step two: let the water circulate good after you refill

Step three: test everything again. Fix pH and TA

Step four through who knows: raise FC to shock level for your CYA. Brush. Retest, Redose. Repeat. The complete instructions are in the SLAM article.


Now tell us your pool is worse than this:

This is the after picture

There's plenty more in this thread. If they can do it, you can do it.

 

[Anna1786]

Thanks so much! I'll post after pics!