Can't get rid of the algae...help

[bponb]

I have lowered my water level twice according to the pool math to get the CYA down. Switched over to liquod bleach for my chlorine. Brushed the pool daily and cleaned the DE filters twice during the process.

Everything seems to be spot on with the pool math calculator. Did the overnight chlorine testing but am still having algae form on the walls. Could I be dealing with something else? Going out now to brush down the pool while I wait for replies.

Thanks in advance.

 

[pwrstrk]

Can you post up a set of test results ? Your using the TF 100 test kit right ?
To rid the algae you need to follow the SLAM Process to the T. If your having algae problems your not keeping your FC in the proper range for the CYA level. ?

 

[duraleigh]

pwtrstrk is on the money. Use that TF-100 and post the results so we can help.

Don't worry, it's nothing else....it's algae.

 

[bponb]

It is currently raining so I will have to wait to give you some up to the moment readings.

 

[pwrstrk]

It is currently raining so I will have to wait to give you some up to the moment readings.

No problem. When you get a chance ?

 

[bponb]

O.K. here are the most recent results

FC= 7.0
CC= 0
TC= 7.0
CH= 200ppm
TA= 100
CYA= 75
PH=8.0
Temp.= 56.3 degrees

 

[pwrstrk]

Everything looks ok except your PH needs to come down and CH could come up a bit.
Let's call your CYA 80. With that you should target FC at 10 and never below 6. What is your target FC ? You should lower that CYA a bit more, but i think you could wait till spring and see where it's at then. If your seeing algae at some point your FC must be slipping below its min. Could be in a spot of poor circulation too.
Let's do an OCLT Test at shock level to confirm if you have organics consuming chlorine. Your shock level is 31. I would also SLAM the pool with any visible algae till all three criteria are met to stop. The OCLT can be the start of your SLAM. Lower your PH into the low 7's to SLAM. I think this should go quickly. How does your water look ?

 

[bponb]

Water is cyrstal clear. Are you suggesting to get my FC up to 31? I will add some acid to get the PH down. According to the pool math I am adding 14oz. Thanks for the info. Correct me if I am doing something wrong.

I have another question. Where are you getting the target of 10 based on my CYA of 80?

 

[pwrstrk]

Yes, take your FC up to 31. That's your shock level. Then do an OCLT Test to see if you have something consuming chlorine. That can also be the start of the SLAM.
I get the target FC level of 10 - 11 from Pool Math's suggested goals. At that FC level it gives you wiggle room from FC burn off so you don't fall below your min of 6 per your CYA level. I always suggest using Pool Maths FC ranges. It's what I use. What has been your FC target when you add bleach. ? ?

 

[bponb]

I am targeting 7 but per your advice I will now use 10 but where are you getting the 10 reading from? Fixen to get the FC up to 31 for the night. Thanks

 

[pwrstrk]

I get the 10-11 from Pool Math. Enter the CYA level of 80 in both CYA columns in Pool Math. Hit calc and in the FC column it will give you that range. It will also be in the suggested FC column. 11 being the high end and 6 the min.
Your target of 7 is too low. That's why your having problems. ?

 

[pwrstrk]

I see from your other thread that your having flow problems out of three returns. That can also contribute to an algae problem along with targeting FC too low. ?

 

[duraleigh]

Water is cyrstal clear

Not really. The presence of algae is not considered crystal clear....despite the fact you can see it easily algae in your pool indicates the need to SLAM.

Fixen to get the FC up to 31 for the night.

That tells me you have not read the SLAM article or understand how the SLAM works (not trying to be harsh, but helpful) Reread the SLAM article and understand that you leave your FC up around 31 until all sign of the algae are gone. Guessing a little but it sounds like you may not be brushing the algae up into the flow of highly chlorinated water as required by the SLAM article.

 

[bponb]

Thanks for the info. I am new to this pool thing so any suggestions are welcome. Helpful tips are encouraged.