Bleach..How Much is TOO much

[Water_man]

Battling green water for the past 8-10 days...pumping in about 2 gallon of 5% daily in hopes things will get better...
Pool is vinyl lined AG and the question:
At what PPM of Chlorine will I start to fade the liner ?? I've been keeping it between 10-16PPM

Thanks in advance folks !

Steve

I won over the green monster in four days by shocking to 20 ppm, brushing, vacuuming and backwashing. I don't have a vinyl liner and I don't know if 20 is safe for you, but you can check. Seems that your FC level is too low - it shouldn't take so long.
My Taylor kit arrived after I had already "won the war". Before that I guesstimated CYA and pH with strips and store tests. The store read my CYA as 56. Taylor read 60.
Also, make sure your pH is balanced around 7.4 because chlorine won't be as active at a higher pH. I also used polyquat algaecide. If you have a robotic cleaner even better. Needless to say pump should run 24/7 and you should keep backwashing your filter, or the equivalent routine with non-DE filters.
Hope an encouragement from someone who had just "been there, done that" helps.

[stma]

Thank You folks..I thought the same about the PPM's being too low, so I increased the bleach...I placed three gallons in, waited an hour and retested..I came up with 15PPM...?? This testing was done after the sun went down
Based on the calculator, this amount of bleach (assume 5.25% and 7000gallon volume, and a 9PPM starting point) should have put me in the 30PPM range....??
Now I'm wondering if the bleach I'm buying: Sho-Brite bleach from Big-Lots is actually 5.25% strength..>>> the obvious answer is to "Read the panel on the container"...but this particular brand does not show percentages....
ANyone using the BigLot's bleach noticing a problem with strength of product ??

[Watermom]

Unless I missed it, I don't see where you have posted a complete set of current water testing numbers. That would be a good idea and may give us some other clues to be able to help.

[stma]

Thanks WMom...
My numbers are all over the place:

FC:20 (Did have a CC number a few days ago, but that is no longer)
PH:8.2 (was 7.0- 10 hours ago) ??
ALK:90

The most important # I won't have till later....the CYA....Although I have been adding a ton of water in the past 10 days or so (to make up for backwashing) and we have been rained on a bit here in Pennsylvania...honestly I cannot see the CYA # being high at all....When I closed down last year, CYA was running @45-50....Unless that number can INCREASE over the winter, I should be OK....

I'm baffled by the PH bounce as well....i thought perhaps the high CL number was causing the increase in PH ??? I don't know....

As always, Thanks Mom for your input...

Your turn :>

[Water_man]

[quote=stma;55491]
FC:20 (Did have a CC number a few days ago, but that is no longer)
PH:8.2 (was 7.0- 10 hours ago) ??
quote]

High FC level gives a false high pH indicator reading.
People use sodium thiosulphate to neutralize the FC but Taylor doesn't recommend it.
Do you have a pH reading of the water before the shocking? If you trust your previous pH reading of 7 I wouldn't worry about pH. The alternative is to check with a glass electrode or a pH meter. Every lab carries one. I'm checking getting one because I don't like comparing colors.

If your CYA is 50, you still need FC =20 to shock, as per chem geek's table and you haven't reached that level yet. I used Walmart's 6% bleach, and so do many others here.


Has your green color changed into blue yet?
Once it does, you know you're on the right track.

Finally, I haven't seen you reporting anything about brushing. You need to keep brushing all the surfaces so that algae sticking to the walls and bottom will be attacked by the chlorine.

[stma]

Ph "was" 7.1 prior to shocking and two hours later I was reading above 8....but if anything I assumed the "pink" in the PH Indicator would have been washed out instead of getting darker....??

Thorough brushing twice a day while shock levels are at their highest..I believe today is 11 days of green, cloudy water...

[aylad]

The bleach sold at Big Lots around here is only 3% strength--might want to call the number on the container and ask what you're using, because if it's the 3% stuff it'll take LOTS to clear up a green pool.

Janet

[Water_man]

Ph "was" 7.1 prior to shocking and two hours later I was reading above 8....but if anything I assumed the "pink" in the PH Indicator would have been washed out instead of getting darker....??

Taylor's Water Chem boolket is clear about high pH false reading. See page 11 if you have it.

The common knowledge is that a high enough FC at the proper pH should kill the green algae. Here's an example which also gives you more tips.
Since the green is persistent, either you haven't reached the proper FC yet, or the pH for some unknown reason is too high, or you have an unusually persistent green monster.
The easiest way is first to make sure you took care of the FC and pH. If this doesn't work I can tell you about my experience with treating "Pink Algae" with Yellow Out.
You can read about it in this thread.

Last season I had pink algae on the walls. The water was clear. At that time I didn't know what I know now thanks to this forum, so when shocking to 5-10 ppm didn't work I was looking for something else. (Little did I know then that I should have tried 20 ppm first, with my CYA of 60.)
Coral Seas has a similar product that works with green algae. It's called Green to Clean.
Check it out here.
Yellow Out did the job, but there are a few drawbacks:

1. You have to start with pH 8. (This was the case with Yellow Out. I'm not sure about Green to Clean.) You are having now uncertainties about your pH. This issue has to be solved.
2. The process works by adding the Yellow Out or Green to Clean and active chlorine together. You already have a supposedly high FC.

If the traditional shocking method doesn't work for you
I'd call Fred as mentioned in my Pink Algae - Yellow Out post and ask for his advice. He doesn't just sell chemicals. He works in the field.
I hope the regular chlorine routine will finally work for you.

[mbar]

High chlorine levels give a false ph reading. That is why it is always recommended to get your ph under control before shocking the pool.