Mustard Algae

[Straightleg]

I have had perfect clear water all summer. The numbers were all good. The only thing high was my ph 8.0-8.2
Two weeks ago added muriatic acid and brought it down to around 7.4
I now have light tan algae on the bottom.
Was thinking on talking my ph back up to 8


I also can't find any of my posts I started. Does that happen automatically when you don't post for awhile?




Thanks SL

[CarlD]

Don't know about the posts. PoolDoc or Watermom should know.

Lowering your pH makes you chlorine MORE effective, not less. But without your FC, CC, TA, CH and CYA readings it's hard to tell.

But raising your pH will NOT kill algae. Raising your chlorine level will.

[Straightleg]

fc 5
cc 0
Cya 60
ph 7.4
ta 120

numbers seem good to me
Have not done anything all summer but add 1/2 gallon (bleach) or alittle less each day.

Only change recent was dropped my ph some

Water still clear, and we have had a hot spell lately



SL

[CarlD]

Sorry, but if your CYA is 60 and your FC is 0, you are BEGGING for an algae bloom--and clearly have one. I would immediately put 7 jugs of 8.25% bleach (if it comes in 121 oz bottles) in your pool and get your FC up to 20. You need to shock your pool to at least 20 and keep it there til it is clear. The ONLY thing raising your pH will do is make it harder for the chlorine to do its job.

Given your numbers and description, the prescription is straight forward.

[Straightleg]

fc 0
cc 5
Cya 60
ph 7.4
ta 120

numbers seem good to me
Have not done anything all summer but add 1/2 gallon (bleach) or alittle less each day.

Only change recent was dropped my ph some

Water still clear, and we have had a hot spell lately



SL


Fixed it:
I typed wrong
My fc is 5
and my cc is o

[FormerBromineUser]

.
Here's a link to your old posts http://www.poolforum.com/pf2/search.php?searchid=48573

FC of 5 is too low for your CYA level anyway. CarlD will give you details :D

[Straightleg]

.
Here's a link to your old posts http://www.poolforum.com/pf2/search.php?searchid=48573

FC of 5 is too low for your CYA level anyway. CarlD will give you details :D



I cant get in to that link. I am locked out for some reason.
My book in the k-2006 says ideal numbers. I am at every one. They say don't let your CYA soar up, so I have been careful with that. Watermom told me to keep it between fc 3-6. I have done that all summer.
So now that you say this I am at a loss



SL

[CarlD]

OK.
Here's what I think happened: Your pH went in to the 8s, effectively shutting down most of your chlorine's ability to perform. (Somewhere we have a table or formula on that).
That allowed algae to form. The answer is STILL to take your FC up to 20ppm (using 5 121oz jugs of 8.25% bleach, instead of 7).

The only other possibility is that something else unrelated to chlorination is going on and it's not algae. But I don't think so.

[FormerBromineUser]

With a CYA of 50, you want to try and keep your chlorine between 3-6 all the time. Here is what to do. Each evening, test the chlorine. Add enough bleach to take your chlorine back up to 6ppm. The next evening, if you find that your chlorine has dipped below 3ppm, take it up to 7ppm when you dose with bleach. The goal is to find out how high you need to take it so that it never drops below the minimum by the next evening. You will soon learn your pool's pattern.

In case you need the Best Guess Chart again, it is here: http://pool9.net/cl-cya/


I think this is the post to which you were referring. Your CYA is now 60 so you need to bump up WaterMom's original minimum recommendation for maintenance.

HOWEVER, you now have algae. CarlD will advise you what to do but in the meantime, reread the Best Guess chart linked above.

Sorry, Carl. We posted at the same time....

[Watermom]

Here is your thread where we helped you get the chemistry going. http://www.poolforum.com/pf2/showthread.php/23760-New-member-pool-owner-for-10-years?highlight=

This is the one about your pool pump hating you! ;) http://www.poolforum.com/pf2/showthread.php/23815-My-pool-pump-motors-hate-me?highlight=

Please let me know if you cannot access these links.

[Straightleg]

OK.
Here's what I think happened: Your pH went in to the 8s, effectively shutting down most of your chlorine's ability to perform. (Somewhere we have a table or formula on that).
That allowed algae to form. The answer is STILL to take your FC up to 20ppm (using 5 121oz jugs of 8.25% bleach, instead of 7).

The only other possibility is that something else unrelated to chlorination is going on and it's not algae. But I don't think so.


Carl My ph has been 7.8 - 8.2 all summer, perfect water clarity. No algae

Algae showed up 2 days ago
I understand to get rid of the algae, I have to pour bleach on it to take my fc up.
I will shock and clean the pool

Then try a 8 to maintain it

[Watermom]

Do your pool walls and floor feel slippery at all? Any chance that it is dirt/pollen/etc?

Go ahead and take your chlorine up to 20ppm as Carl suggested above and while the chlorine is high, brush the pool.

You don't want to keep your pH at 8ppm. Honestly, that is not the thing that will keep you algae free.

[Straightleg]

Do your pool walls and floor feel slippery at all? Any chance that it is dirt/pollen/etc?

Go ahead and take your chlorine up to 20ppm as Carl suggested above and while the chlorine is high, brush the pool.

You don't want to keep your pH at 8ppm. Honestly, that is not the thing that will keep you algae free.


Maybe it is pollen. Everyone has been sneezing lately
When I say 8, I mean my fc...instead of 5...that ok

[Watermom]

Ok. I thought you meant pH of 8. My bad.

If everyone is sneezing, I bet it is pollen. I just did a google search for 'pollen counts southern ohio' and found a page on the Weather Channel's website that lists it for various cities in the state. I didn't know what city you were in so I just put Cincinnati in and it said moderate to high.

You can try it. Here is the link. http://www.weather.com/outlook/health/allergies/drilldown/ohio
Then, just click on the first letter of your city's name and you'll be able to find the pollen forecast for your area.

But, having said that, still feel the floor the next time you are in the pool and see if you note any slipperiness.

Hope this helps.

[CarlD]

Lisa, she did say pH was high and that she thought it dropping caused the apparent bloom. Also that she maintained pH between 7.8 and 8.2 all summer.

If your pH has been that high all summer, then unless your FC was at the TOP of the recommended maintenance range for your CYA, or higher, then you've been, in my opinion, lucky not to have had a bloom sooner. If your borate level is fairly high and you regularly put in Polyquat 60% it may have inhibited algae growth. Or you just may have been lucky.

But if your CYA is 60 and your FC fell to 5 while your pH was 8 or higher, those numbers work for an algae bloom. It's easily within the range of probability. And once it starts, a normal maintenance range won't stop it.

Now it is also possible you have a lot of pollen, and frequently the stuff is yellow. Allergy season is back on us with a vengeance and even I, who have fairly few allergies, have been suffering.

[Straightleg]

Last time I looked I was a he...(:
I guess I have been lucky then having clear water. with fc around 5 and cya of 60
I shocked and swept the pool. Took FC up to 20

This could have been dirt and pollen. It did not rain for awhile and yes I live in Southern Ohio. I don't have allergies but many around me do and said it is bad for them.


I will keep PH down to 7.4


Thanks
Gerry

[CarlD]

Last time I looked I was a he...(:
I guess I have been lucky then having clear water. with fc around 5 and cya of 60
I shocked and swept the pool. Took FC up to 20

This could have been dirt and pollen. It did not rain for awhile and yes I live in Southern Ohio. I don't have allergies but many around me do and said it is bad for them.


I will keep PH down to 7.4


Thanks
Gerry

Whoops! Mea culpa! Sorry 'bout that....:sad:

[FormerBromineUser]

Goals: 7.4 pH and 20 FC. Sounds like a good plan, MR. Straightleg. Post updates!

[Watermom]

Don't fight your pH to try to keep it exactly at 7.4. Some pools just naturally want to be a little higher. As long as you are 7.2-7.8, you are fine.

[FormerBromineUser]

Good point. Btw, your email address apparently needs updating. You can do this in settings at the top of this page. Maybe that's why you can't see your posts???? Not sure but worth a try.