# Green Cloudy Water

#### laren

For the past month we have had and off and on algae problem. I ordered one of Dave's TF100 Kits and the results are as follows:

FC - 9
CC - .5
PH - 7.5
TA 180
CYA 58

ag 18' round 6500 US gallons, sand filter

I used Jason's pool calculator and the results were 22oz. of muriatic acid or 12 oz. of PH down to lower the TA level and to get rid of the Algae 119 oz. of 5.25 bleach to shock. How long do I have to maintain this level of 14 ppm to get rid of the Algae and what is a safe level of FC for swimming? The weather here in Ontario is very hot

#### The Mermaid Queen

TFP Expert
You need to maintain the FC until:
1) Your FC level will hold overnight
2) you have 0 CCs (or less than 0.5
3) your water is clear

With a CYA of 58, you really need to shock to 18.

Safe level for swimming? that question will have varying answers here. Some will say don an old suit, and rinse off promptly, and high FC is ok. Others say let it drop to the normal range (for you 5-9). I fall into the first camp, provided the water is decent-looking and there are no cc's.

#### laren

How do I calculate my shock level? You gave me a number of 18 but I don't know how to get that number

Thanks

#### edbson

##### Well-known member
Add 125 OZ of 6% bleach to get your Chlorine to 18(shock level). Test water several times daily to maintain shock level until pool clears.

Pool calculator
http://www.poolcalculator.com/

#### edbson

##### Well-known member
Because the Higher the CYA, the higher the shock level is.

#### Buggsw

If you use Jason's calculator JasonLion's Calculator and fill in your current readings, it tells you what your shock level is at the bottom of the page.

Also, there are stickies around that point to "Ben's Best Guess" chart which shows the ideal FC and Shock levels based on the amount of CYA in your pool.

#### laren

Thanks Buggs, I never saw the chart at the bottom of the page. I noticed that there was something called CSI and mine is at .15 is this something to be concerned about and if so do you know how I lower it? I made a mistake on water total for my pool, it's 6500 not 6700. Last evening at 7:30 I added 143 oz. of 5.25 bleach and then retested at 10:30 and had to add another 79 oz. My FC reading this morning is 22.5 and CC is 0.

#### laren

I've maintained a high FC level since Friday evening and we still have algae I haven't added bleach since Friday because my FC level held over 18. All I added yesterday and today is PH down, Im trying to lower my TA so I'm keeping my PH around 7.0 Could it be that the algae goes through the sand filter and back into the pool (we vacuumed and backwashed)? My readings this morning are.

FC 16.5
CC 0
PH 7.4
TA 180
CYA 50

I appreciate the help!
Thanks

#### Buggsw

Are you brushing your pool every day during this clean up phase? You should be.

Are you actually seeing green algae or dead white algae clouding your pool? If it's white, it's dead and normal.

#### laren

yes we have been brushing the pool. We will vacuum and backwash again in a couple of hours and see what happens. The algae is a greenish yellow colour. It does vacuum up and then starts returning a short time later. I don't think it's pollen because our next door neighbour has crystal clear water. We managed to get rid of the algae last weekend for a couple of days and then it returned but during that time the water was still cloudy. Is it the high TA that clouds the water?

#### The Mermaid Queen

TFP Expert
Maybe its mustard algae??? For mustard, you need an even higher shock level to kill it.

With CYA of 50, you need 16 to shock and 29 to shock for mustard. (if your CYA is closer to 60, like the 58 you first listed, you need 18 to shock and 34 for mustard.)

#### laren

When I tested this morning my cya level was at 50, but we had emptied 1/3 of the water from our pool on Friday before shocking it to try and bring the TA down.

I guess we could have mustard algae...but wouldn't it be eating up our chlorine? I can't seem to get the FC to come down so we can use the pool.

#### Buggsw

Sounds to me like it's just stuff returning from the filter.

Try putting a skimmer sock on the return/s - maybe use some twist ties or something to keep it on there.
You could try adding a little DE to your skimmer, so your filter filters better. Add just enough to increase the pressure 1 lb.

#### duraleigh

Platinum Supporter
TFP Expert
In The Industry
laren,

Chlorine will clear your pool. Whether you have green algae, mustard algae, or ketchup algae :lol: ......CHLORINE WILL CLEAR YOUR POOL

The guy from whom most of us learned used to say "your pool didn't get in it's condition in a day or two....don't expect to cure it in that time frame" It's still good advice.

Keep your chlorine levels high (above 20 but probably not above 30 or so) and brush and vacuum and keep your filter clean and pump running.

Tomorrow, keep your chlorine levels high, brush and vacuum and keep your filter clean and pump running.

Tuesday, keep your chlorine levels high and brush and vacuum and keep your filter clean and pump running.

I know I'm being obnoxious but I want to make a point....there's nothing else in your numbers that is dangerous or causing your water problems. What you are doing is a slow killing and clearing process that is bulletproof unless you get sidetracked on some peripheral issues.

Give it a few more days but don't get sidetracked.....your water will clear up if you do the above.

(if it doesn't, I will make one more post blaming the whole thing on SeanB and then I will become very scarce on the forum!! :lol: :lol: )

#### edbson

##### Well-known member
Dave is right, got me from swamp water to sparkling blue inside of two weeks!

#### MikeInTN

TFP Expert
duraleigh said:
(if it doesn't, I will make one more post blaming the whole thing on SeanB and then I will become very scarce on the forum!! :lol: :lol: )
Classic!! :lol:

#### laren

Thank you Dave.....I received my test kit last Thursday (it only took 5 days!) and I don't know how I managed without it!

I will keep the Chlorine level high for the next few days, but it concerns me because it doesn't drop. I shocked on Friday evening and on Sunday afternoon the FC was still 16. I'm going out now to do another reading, I'll keep you posted.

Thank you,
Laurie