New Pool - how am i doing and high TA?

[kabz]

We just installed a new vinyl inground pool, 25,000 gallons. Water sat for about a week before we could get pump started yesterday. Was very cloudy and can't tell if algae starting on floor and walls or sand in pool from back fill. Vaccuumed yesterday but couldn't get it all. It is definately a film. You can see where you vacuum/brush. Will brush into "piles". I am off to vacuum again.

Chemicals -

I have added 104oz of bleach, Shock'nSwim, 32oz dichlor and 4 pounds of stabilizer.

Today test results are:

TC 8.6
CC 0
pH 7.8
TA 310
CYA 20 (but just added yesterday, so won't totally show up yet, right?)
CH 420

What should I do now? Water is much less cloudy this morning. Our water is HARD here, so that didn't surprise me. What should I do about the TA?

 

[JohnT]

Welcome to TFP!

You should get your chlorine level up to 10ppm and hold it there until you are convinced the algae is under control.

Where do you live? Rainfall can be a big help in controlling TA and CH, so how aggressively you pursue lowering TA may depend on your location, but your CSI is fairly high, which means you need to keep your pH low and try to reduce TA to prevent scaling. There is a Pool School article on calcium scaling that you may wish to read.

 

[kabz]

We live in Iowa. Not a lot of summer rain and very little this year.

 

[JohnT]

But you'll get rain in the winter, and that can help dilute your high CH and high TA. Stay on top of your pH, and choose a winter cover that allows rain water into the pool. if you can keep your pH down around 7 or 7.1, your TA will naturally decline and you'll avoid scaling. It will go faster if you aerate. Here is a link to the Lowering Total Alkalinity article.

Replacing water with lower CH water is about the only way you are going to drop your CH where you live, so rainwater will be your friend.