Cloudy gone, new problems now

[lskeate]

I felt like I had won the lottery when I found you people last week. Here is a brief synopsis of our problem:
20,000 gal fiberglass, cartridge filter with new cartridge. Water was cloudy and pool store had us adding muriatic acid by the gallon (>250, no printout) Then the green tint. Treated with very expensive algaecide and floc and nothing. Now very green. New pool store and less expensive algaecide and clarifier and after vacuuming to waste, no green, but back to cloudy. Lost faith in pool store and found YOU! Used 5, 1.4? gallons of clorox on Saturday and left the pump running. Water looks great now, but a beautiful color of blue it's never had. What does that mean? Back to pool store #1 yesterday, told them what I did and received a cool reception. They did run the water for me:
FC 7.8
TC >10
CC 2.2
pH 7.6
Hardness120
Alkalinity w/stabilizer correction 82
Cyanuric Acid 95
Now they want me increase my alkalinity (after all those gallons of muriatic acid) and increase hardness with Ca hardness increaser.

What do you wise people suggest I do? I haven't been a very quick study for the pool chemistry thing. But I'm reading old threads and learning slowly. Thanks for all the wisdom out there.

[Watermom]

Glad it is looking better. The biggest problem I see is that high cya (stabilizer) reading. At 95, you are going to have to keep your chlorine high all the time or you are going to have a repeat of your algae problem over and over. Take a look at the following chart.

Ben's 'best guess' FC/Stabilizer table for algae free operation of OUTDOOR pools -- as of July 2003 --

Use the info in this chart to help you figure out what levels of chlorine you need to maintain in your pool based on the amount of CYA (cyanuric acid, also called stabilizer) that you have in your pool. (FC = free chlorine)

Stabilizer . . . . . . Min. FC . . . . Max FC . . . 'Shock' FC
=> 0 ppm . . . . . . . 1 ppm . . . . . 3 ppm . . . . 10 ppm
=> 10 - 20 ppm . . . . 2 ppm . . . . . 5 ppm . . . . 12 ppm
=> 30 - 50 ppm . . . . 3 ppm . . . . . 6 ppm . . . . 15 ppm
=> 60 - 90 ppm . . . . 5 ppm . . . . . 10 ppm . . .. 20 ppm
=> 100 - 200 ppm . . . 8 ppm . . . . . 15 ppm . . .. 25 ppm

We like to suggest cya readings of 30-50. You have two options. One is to keep it at 95 and just maintain higher than normal chlorine readings. The second is to do a partial drain. If you exchange 50% of your water, that would put you at a good cya level. Your choice. Either way will work.

If you decide not to do a partial drain, then you should continue shocking your pool up to 20 or so until you get rid of that CC reading. Test at least 2 and 3x times a day is better and each time, raise your cl back up to 20. Also continue to run the filter 24/7.

Either way, your alk and calcium hardness readings are fine. Keep us posted about what you decide to do. Welcome to the forum!

[lskeate]

That chart is what sent us to the grocery store for Clorox. But according to the "pool store", I don't want to swim in TC of 10. I assume that with the Cyanuric acid level as high as it is, if I keep chlorine as high as the chart suggests, I can still swim or you would be suggesting the drain immediately.

Also, why the wild shift in Alkalinity in a two week period? I only got a C in college chem, but the husband is a chem major. He'll understand the explanation. Thanks for your help. What did people do before the internet?

[Watermom]

With a cya of 95, it doesn't hurt to swim in cl of 10. I wouldn't swim with cl at shock level however. Are you going to just run high cya and high cl or do a partial drain? Not sure why the swing in alk.

[duraleigh]

It's not clear to me if you're still trying to get your water crystal clear. I think you are but please post back and confirm that before we reccommend a plan.

[lskeate]

This is the real deal. Maybe. The pool is very blue, a color I'm not familiar with. My inclination is to tell you it's not cloudy any longer, but the blue color really is throwing me for a loop. The fiberglass is not blue, but white. (And now appears to have stains, but that's another thread for another day) So let's assume it's clear.

I am now the proud owner of a 5-way WalMart test kit. These are my results as of 10 minutes ago.

CL-Orange
Ph-7.5
Alkalinity-after 60 drops changed only to a champagne color
Cyanuric-below the mark. Maybe 3/4 inch of solution covered the dot
Hardness-indicator turned water pale, pale, barely there champagne

Not very similar to the pool store results of yesterday. How many square yards of dirt does it take to fill in a 20,000 gal pool?