Draining and replacing vinyl liner swimming pool water

Hello - I've had a heck of a time last spring and this spring with opening my pool with cloudy water. I've already put in roughly 40 gallons of chlorine with no readings on the chemical indicator and no visible change in the cloudy water. The PH is around 6.8 and I am trying to raise it with Borax and infusing with oxygen with the "sprinkler" system. The PH is also very sluggish and doesn't want to increase.

It is a vinyl liner pool that is about 9 years old with the original liner. I've never replaced the water and I think that it is about time. What is the best and safest way to replace the water in my pool to "start over" with fresh water?

Thanks, Ross

Hi Ross, and welcome!

It's hard to tell what's going on without any real information on your pool and your water condition. All I can tell is you have a vinyl pool and cloudy water.

It will be helpful if you can tell us:
In-ground or Above Ground
Gallons.
Pump size
Filter type and size (if possible)
and
....
Actual readings of the water.
Chlorine levels (preferably divided into FC--Free Chlorine and CC--Combined Chloramines)
pH
Total Alkalinity
Calcium Hardness (for reference--not important in vinyl pools unless it's too high)
CYA/Cyanuric Acid/Stabilizer/Conditioner.

Our first recommendation is always a good test kit, not guess strips.
We recommend the Taylor Technologies K-2006 or K-2006C kit, available via the link on PoolDoc's signature.
The Leslie's FAS-DPD Chlorine Service Test Kit available on-line is the same as the Taylor, but re-badged with Leslie's name and quite a bit more expensive.

In the interim, there's an inexpensive Wal-Mart kit that will do most of what you need:
http://www.walmart.com/ip/HTH-6-Way-Test-Kit/17043668

I'd get a gallon of Steam-Distilled water as well so you can use the "CarlD Patented Shot Glass Method" (a joke name for a valid method) for doubling, tripling, or quadrupling the range of the OTO chlorine test.

Run the tests with the Wal-Mart kit for now and post the results. Alternatively, take a water sample to a pool store and post THEIR results, but don't let them talk you into buying anything just yet.

Good luck!

Carl's advice is correct, but to directly answer your HOW-TO drain a vinyl pool question, there are 2 methods:

1. Hire a vinyl liner installing company to drain it, without destroying the liner. Do NOT try this yourself: you do NOT have the equipment.

2. Drain in place, using ropes, a small sump pump, hoses, and a VERY large plastic tarp.

But . . . do what Carl said, first. It may not need to be drained.

Quote:

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Originally Posted by CarlD

Hi Ross, and welcome!

It's hard to tell what's going on without any real information on your pool and your water condition. All I can tell is you have a vinyl pool and cloudy water.

It will be helpful if you can tell us:
In-ground or Above Ground
Gallons.
Pump size
Filter type and size (if possible)
and
....
Actual readings of the water.
Chlorine levels (preferably divided into FC--Free Chlorine and CC--Combined Chloramines)
pH
Total Alkalinity
Calcium Hardness (for reference--not important in vinyl pools unless it's too high)
CYA/Cyanuric Acid/Stabilizer/Conditioner.

Our first recommendation is always a good test kit, not guess strips.
We recommend the Taylor Technologies K-2006 or K-2006C kit, available via the link on PoolDoc's signature.
The Leslie's FAS-DPD Chlorine Service Test Kit available on-line is the same as the Taylor, but re-badged with Leslie's name and quite a bit more expensive.

In the interim, there's an inexpensive Wal-Mart kit that will do most of what you need:
http://www.walmart.com/ip/HTH-6-Way-Test-Kit/17043668

I'd get a gallon of Steam-Distilled water as well so you can use the "CarlD Patented Shot Glass Method" (a joke name for a valid method) for doubling, tripling, or quadrupling the range of the OTO chlorine test.

Run the tests with the Wal-Mart kit for now and post the results. Alternatively, take a water sample to a pool store and post THEIR results, but don't let them talk you into buying anything just yet.

Good luck!

---

Thanks Carl! I'll get the numbers and post them on here. This is an awesome forum!

Ross

We try! It takes a whole bunch of us to keep it awesome! We've got chemistry geeks, pump geeks, metal (in water) geeks, plumbing geeks, solar geeks, heater geeks, construction geeks, etc!

Information for my pool with cloudy water:

In-ground 18'x36' vinyl lined pool roughly 9 years old
29,000 gallons
Pump size = 1HP
Filter = Hayward Sand S240 (replaced sand end of last year)

Actual readings using the Walmart HTH 6-way test strip:

Chlorine = < 0.5 ppm (after dumping roughly 40 gallons of chlorine in 2 weeks)
pH = 7.0
Total Alkalinity = 130 ppm
Calcium Hardness = < 200 ppm (water started out blue from kit)
CYA = 80 ppm

The current condition of the water is cloudy enough to not see the 4' shallow bottom of the pool. I have been oxygenating the pool with homemade return PVC pipe sprinklers to raise the pH without raising the Alkalinity, as well as using borax. The pH is going up VERY slowly. I am also filling an in-line chlorinator with 3" chlorine tabs to keep a steady stream of chlorine into the pool.

So the question is.......should I drain and replace SOME of ALL of the pool water? Or do you think that I can get this under control using chemicals?

Thanks in advance for your great help!!

Ross

You probably should do the chlorine demand bucket test, to see how much further you have to go: http://pool9.net/bucket-demand/ =>

Ben has already suggested you do a bucket test. I just have a comment to add regardless of what the bucket test shows.

If it were my pool and I had a CYA of 80, I wouldn't be using pucks at all, ever. I'd use bleach instead. Pucks will continue to add CYA and yours is plenty high enough already! Besides to clear a pool up, you can't add a large enough dose of chlorine with trichlor pucks.

You should be able to solve your problem by adding 7 gallons of 8.25% bleach at a time, and checking your chlorine level 3x / day. Your goal should be a chlorine level of 20ppm and each gallon of 8.25% should add about 2.84ppm of chlorine.

If you use 12% liquid chlorine, it will add about 4.1ppm per gallon and you'll need 5 of them to shock your pool (that's one full 5 gallon carboy).

40 gallons sounds like a lot, but if you didn't add it in large enough increments, your algae would just keep coming back. Since MY liner is old and faded, I'm willing to get my chlorine levels quite a bit higher to slam that algae to death.

Thanks everyone! I need to get some additional borax and try out the bucket test tomorrow. I'll post what I found out.

Ross

Well I didn't do the bucket test, but I did drain about 1/8 of the water out of the pool and replaced it....and then kept at the chlorine morning and evening, and now it is finally clear. Either at the end of this season, or at the start of the next I will have the liner replaced.....along with the water! That will help things, I'm sure!

Thanks for everyone's help, and keep up the great work on this forum!

Ross

Glad thinks worked out for you!

I love it when a plan comes together!