Cloudy Bright Blue Pool Water Please Help!

[moselem]

I have a 18x36 inground pool with a vinyl liner. The pool holds 25,000 gallons. I have been trying to get the pool usable for close to a month now and am still not having any luck. After many trips to the pool store I finally bought a test kit myself. The pool started out dark black and smelly, I added 17 gallons of bleach which helped some. Since then I have added LOTS of powder shock, algecide, ph increaser and clarifier. The pool is now a bright blue color but not clear at all. After another pool store trip they had me add (this was yesterday) 2 pounds of granule shock, 4 pounds of soda ash and clear and perfect 6 way clarifier. These are my current readings.

FC - 1

TC - 3

PH - 6.8

Alkalinity - 110

CYA - 70

Needless to say I need help! The pool currently has particles floating through the water that I can actually see if I get down close to the waterline but they look very fine. I also have a Hayward chlorinator that is currently set on 5 and is using about 5 tabs every 5 days. I have backwashed it several times over the last month and used the brush on it but I have not vacuumed it any.

[waterbear]

I have a 18x36 inground pool with a vinyl liner. The pool holds 25,000 gallons. I have been trying to get the pool usable for close to a month now and am still not having any luck. After many trips to the pool store I finally bought a test kit myself. The pool started out dark black and smelly, I added 17 gallons of bleach which helped some. Since then I have added LOTS of powder shock, algecide, ph increaser and clarifier.

Stop adding unnecessary chems and let's get a handle on the situation. Is your test kit chlorine test an FAS-SPS chlorine test (titration test), a DPD test (turns red and uses a color comparator), or OTO(turns yellow and uses a color comparator)? I assume you can also test for pH, TA, CYA and calcium (not total) hardness. What is the make of your test kit?

The pool is now a bright blue color but not clear at all. After another pool store trip they had me add (this was yesterday) 2 pounds of granule shock, 4 pounds of soda ash and clear and perfect 6 way clarifier. These are my current readings.

Lets look at your test results and see what needs to be done and in what order. The good news is your TA is fine at 110 and you have a vinyl pool so calcium is not an issue unless it is very high. Might be worth testing it and making sure it is not above 400-500 ppm. Anything lower should be fine.

FC - 1

TC - 3

PH - 6.8

Alkalinity - 110

CYA - 70

First, you need to get your pH up. 6.8 is the lowest limit on most test kits and it is possible that yours is actually lower than that! That low a pH can damage your vinyl liner. I would use borax to raise the pH (the stuff in the green box in the laundry aisle of the grocery store) since your TA is fine at 110 ppm and you really don't want to raise that. pH increaser will raise both pH and total alkalinity. If you are worried about adding borax to your pool, don't be! Pool stores sell it for a lot of money under such names as Enhance, Optimizer, and Supreme as an algaestat and water enhancer! You will need about 10 lbs to raise the pH to 7.6, assuming your pH is really at 6.8 and not lower. I would put in 1 whole box (4.75 pounds poured right into the skimmer), wait about an hour and test your pH to see how much it rose. It should be around 7.3. If it is add another box and then retest in about an hour. If your pH is not at least 7.4 by now then add no more than half a box at a time to get it there and then stop for now. you can make minor adjustments to your pH after we take care of some of the other problems.

The next thing I would do is a partial drain and refill to lower your CYA much closer to 30 ppm. With a vinyl pool you don't want to drain much more than maybe a foot below the skimmer at most so you are talking about several drain and refill cycles until the CYA tests in range. The trichlor tablets in your chlorinator add CYA with every tablet and that will overstabilize your pool. Your chlorine will not work as well and you will need to run it at a much higher level and shock to a higher level to get the same effect. Your other alternative is to stop using tabs and start manually dosing with liquid chlorine or bleach (same chemical, different strength. You will need about twice the amount of 6% ultra bleach to get the same ppm FC as 12.5% liquid chlorine. If you continue to use tabs your CYA will just continue to rise. At a 70 ppm CYA level you need to maintain your FC between 5-10 ppm for normal chlorination and shock to 20 ppm! If you try to do this with trichlor tabs your CYA will shoot through the roof very fast! If you get your CYA in the 30-50 ppm range you need to maintain a 3-5 ppm FC and shock to 15 ppm, much more do-able!

Next, once the CYA is under control you need to shock your pool to the proper level (SEE ABOVE) and MAINTAIN THAT CHLORINE LEVEL UNTIL YOUR CC GOES TO 0 AND YOUR FC READING IS HOLDING OVERNIGHT! That means testing and adding UNSTABILIZED chlorine (liquid, bleach , or cal hypo if your calcium is not too hgh) at least morning and night, 3 or 4 times a day will make it go much faster. If you use 12.5% liquid chlorine then every pint and a half will raise your FC about 1 ppm (actually closer to 26 oz but pint and a half is close enough for government work!)

If you are using 6% ultra bleach then you will need a bit over 1 1/2 quarts to do the same (1 1/2 quarts and 5 oz)

If you are using 5.25% regular strength bleach you will need 1 3/4 quarts and 5 oz to raise your pool 1 ppm FC. Test your FC and add enough to raise it the rest of the way to 15 ppm (assuming you have gotten your CYA between 30-50 ppm) and test it at least morning and night and adding enough liquid chlorine or bleach to maintain that level until your FC holds overnight and the pool starts to clear. If there is any stuff that you can vacuum out do so to waste before you start this! Get as much of the organic stuff out of the pool first and the process will go much faster.

Once your FC is holding and there is no CC then you are done. Just let your FC drop and maintain it between 3-5 ppm and let your filter clear the pool It might take a week to do so but it will.

Needless to say I need help! The pool currently has particles floating through the water that I can actually see if I get down close to the waterline but they look very fine. I also have a Hayward chlorinator that is currently set on 5 and is using about 5 tabs every 5 days. I have backwashed it several times over the last month and used the brush on it but I have not vacuumed it any.

Once you are done and the FC is in the 3-5 ppm range recheck your ph and adjust to about 7.6 and then check your TA. TA should still be in range but if it's too low baking soda will raise it.( Baking soda is EXACTLY what the pool store sells you as total alkalinity increaser!)

Hope this helps.

[moselem]

Wow! Thanks. I'll let you know how it goes.