help newbie

[hannadock]

I have a inground vinyl 20X40 pool all of my test are within range BUTeach day I come home and algae is appearing again. I scrub the walls and floors and then vacumn on waster after everything settles. The next day same thing it slowly appears. Also I notice when I added boric acid 20 mules in the beginning it seems that the water cleared but once someone starts swimming the water is no longer clear. I turned off my pump during the day and run it from 6p to 7a each day. What am I doing wrong. Also super shock is that not the same as bleach. thanks for any help in advance.

[duraleigh]

Hanna,
Please post a set of test results for:

FC
TC
pH
Alk
CYA

Without them, we're only taking guesses as to your problem.

[hannadock]

I hope that I have read these right using aqua-chem and a bio-lab kit for the ph.

fc 1.0 to 1.5
tc 3.0
ph 72.-7.4
alk 160
cya 60

I have not replaced the sand in this filter in over 10 years.
Thanks

[duraleigh]

Hi, Hanna,

Thanks for the numbers...it appears you did them just right.

You can get your pool clear with Clorox..you won't require anything else but you'll probably need quite a bit of it.

1. Download mwsmith2's bleachcalc from any of his posts. Put it on your desktop...you'll use it all Summer.

1a. Run your pump 24/7 during the process below.

2. Using the bleachcalc, put in enough Clorox to bring your Cl up to 20-22ppm for your first dose. Measure and calculate accurately.

3. Test for Cl as often as you can and each time you do, add enough to bring it back up to 20ppm. So if you test 6ppm, add 14ppm to bring the total to 20ppm. Keep doing this as frequently as you can (two or three times daily is good....testing and adding when the Sun is down is even better.) until your water stops showing signs of algae...it may take a few days.

4. You may need to backwash your filter frequently....particularly the first day. Do it when the pressure rises more than 5psi or so from it's normal range.

5. Once your water looks like you want it and you have no indication of algae, Stop adding Cl and let it drift down to about 5-6ppm.

6. Once it gets down to 5-6, you must keep it between 5 -10ppm all the time and your algae issues will be over.

Post back with questions. Your sand is fine....don't mess with it unless you have some other reason than algae to think you have a filter problem. This whole process may take a few days....be patient and keep adding Cl.

[hannadock]

Thanks. I am going to change out the sand this week. It's overdue. Need a new gauge as well. What is the difference between Super Shock and Bleach?

Thanks

[hannadock]

Sorry missed the part about the sand. It is well over 10 years old. I may hold off and see how everything goes based on your response. thanks again