Green water, broken filter, big party scheduled, what to do?

[collgirl]

Here we go.

I have a 45000gal in ground SWG vinyl lined pool.
Followed the BBB methods and have had spectacular water.
Went away for long weekend.
Upon return water level was several inches low.
Refilled with well water(first time using well to fill pool) while kids swam.
Wife came home from work and wanted to go for a dip, said water was green and too cold. Please turn pump and heater on.
I turned the pump on and found the source of my low water. The body of sand filter was cracked and produced a geyser.

Pool store ordered new filter under warranty, be here in a week. Need to shock pool.

Over a period of 4 days I shocked the pool, first up to 24ppm for two days, then up to 36ppm for two days. No change noticed. My pump will recirculate and I have an endless pool so I have good mixing.

Pool store said to use flocking liquid then vacuum to waste. No change noticed. No precipitate to vacuum.

Took water sample to second pool store, tests show no iron or copper, but ph up to 8.4. I added 2.5 gal muriatic acid.
Now waiting to re-test ph.

I surmise that something in the well water has caused my pool water to turn green. Water is clear and colorless to about 3 feet in depth, below 3 feet it gradually turns green, but still clear.

Whatever it is that is coloring my water should not be organic because, my chlorine levels have held very well and there has been little precipitate filtered with my robot.

So, any ideas what this is, and can it be eliminated without the use of my sand filter? Naturally, the new filter will not be online before my sons Marching Band party on Thursday, 8/13/09.

Thanks in advance for your help!

Edited for more natural font size. JasonLion

 

[JasonLion]

Welcome to TFP!

We need a full set of water test results before we can tell you how to solve the problem. Also, when you say the water is green, is that a cloudy/murky green or a clear sparkly transparent green?

If the water is currently cloudy and the filter isn't working, the only way to clear up the water is with floc and vacuuming to waste (which is a pain and doesn't always work). And that is assuming that any algae is in fact dead.

 

[JohnT]

Took water sample to second pool store, tests show no iron or copper, but ph up to 8.4. I added 2.5 gal muriatic acid.
Now waiting to re-test ph.

Your high chlorine level is interfering with the pH test. Don't adjust it until you have a normal chlorine level.

 

[MikeInTN]

Took water sample to second pool store, tests show no iron or copper, but ph up to 8.4. I added 2.5 gal muriatic acid.

I surmise that something in the well water has caused my pool water to turn green. Water is clear and colorless to about 3 feet in depth, below 3 feet it gradually turns green, but still clear.

Hmmmm..can you take a sample of your well water and have that tested? Or get a second opinion at another pool store? This sounds like a classic case of iron in the water. The iron will cause the water to turn yellow, and against a blue background (like your liner) looks green.

 

[collgirl]

Hey guys,

Thanks for your prompt replies! I went back to the second pool store and had them retest my water. They also gave me an adapter for one of my returns and suggested that I zip tie an old t-shirt to it just to see what it might collect. They said to block one of my three returns off, use t-shirt filter on the second and leave the third alone.

Test Results
Sat. index 0.4
TDS 500
CYA 0
Tot CL 10
FC 9.8
pH 8.3
Tot alk 68
Adj Tot alk 68
Tot Hardness 121
salt 3400
Borates 54
Copper 0
Iron 0
Manganese none
Cloudy no
Staining no

pH strip at store tested low, and home test reads 7.2. CYA tests 60 at home. FC tests 24 with drop test.

Water is still clear and green.

Hope this info helps.

Thank you

 

[dlduvall]

Before we found BBB, and before we added a water softener system to take care of our hard well water, we had this same issue every time we added water to our pool. It would turn a shade of green (but not algae) by the next day after the top off. PB said it was because of the iron in our water. We had to add a product called Metal Out every time we topped off. Don't know what was in it exactly because we didnt know to look at label back then, but it worked.

 

[JasonLion]

Assume the test results are right, your first priority is to get the PH down to around 7.5. It is important to keep PH below 8.0 if at all possible and ideally between 7.5 and 7.8.

You also should add some CYA to around 30 to 40. Without any CYA in the water you will lose all of your chlorine very quickly any time the sun is out.

The green is most likely from metals in the water, combined with high FC, high PH, and low CYA. Adding CYA and lowering the PH will very likely get rid of the color. If that isn't enough you will need to use some sequestrant.