I don't have pictures and I scrubbed the pool yesterday and it basically disappears at that point. I am planning on scrubbing daily for the time being.
Just can't get rid of the algae
- Thread starter Snowshoe
- Start date
Maybe NOT A GOL DARN ONE of us gets the googley eye test right.
I have the old 30 ml CYA view tube and the new 15 ml tube and they are consistantly 20 ppm off from each other. *Then* subjective human error comes into play.
I think I run hot enough to account for that, or me, but if algae started poofing, i would run hotter without blinking.
Another thought @Snowshoe. Have you failed an Overnight Chlorine Loss Test ? 'Visible algae' to me is vague at best, especially this time of year. I mean. If green gunk is clearly growing up your stair trim or skimmers, then ok. But I've had a poofy floor for a month now since nature started shedding. I had similar on a heavily wooded property, and also now on an open one abutting a farm. If I brush after a breezy day on the book ends of the season, it's gonna poof. I often wonder how many people have both going on, and their slam was extended for 7 to 10 days based upon the environmental poofing. (Failing only the visible algae criteria) Eventually there's no more pollen/crud and it appears persistence won the battle, when only time was needed at that point.
Whenever I wonder, I pass an OCLT with flying colors, .5 loss or less, and then I don't wonder again for a week or two. If my FC is not already plenty hot, I bump it in the meantime.
Whenever I wonder, I pass an OCLT with flying colors, .5 loss or less, and then I don't wonder again for a week or two. If my FC is not already plenty hot, I bump it in the meantime.
> Its truly as simple as that.
That's what I was believing going into this months ago but unfortunately not everything in life is that cut and dry. It may be as simple as that for most cases similar to this but, in science (and many other aspects of life) there are almost always exceptions. That is why there is a whole page on this website on the particular problems of mustard algae.
If you read my original post I stated:
"I did a SLAM this summer which took about a week and I performed it by the book and ended when there was no sign of the algae, CC was 0 and OCLT was 0. In about 3-4 weeks the algae was back again.
+
I assumed I somehow did not keep the SLAM going long enough so I performed a 2 week SLAM which I kept up for about a week past where the 3 tests indicated I was good to stop. I also kept the FC levels elevated for several weeks after the SLAM – nominal FC is 5-7 (CYA 40) and I have kept the FC between 9-11 post-SLAM. The algae returned again about 3 weeks after I ended the SLAM even though the FC never went below 9."
I doubled the length of the second SLAM going an additional week after passing the OCLT and then after that kept the FC in the 9-11 range and often higher. The result? Algae came back. Not so simple.
- Jun 7, 2017
- 10,021
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
My neighbor's pool had what we thought was a stubborn algae problem a few years ago. We kept adding chlorine which would not remain in the water. Turns out, he had bacteria that had consumed the CYA and created ammonia as a byproduct.
I appreciate the thought but yes I have failed an OCLT. I have failed them during the SLAM and pass them eventually after a period of time. I am leaning toward the mustard algae theory which requires raising the FC level even higher that the SLAM level. Chlorine/CYA Chart
Interesting. Do you know how he diagnosed it? And how did he resolve it?
- Jul 17, 2019
- 4,085
- Pool Size
- 13000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Sure it is. FC of 9-11 doesnt work for your pool in its current state, so your demand for chlorine is higher than that, unfortunately.
If I had to bet, it would be hidden algae somewhere (behind lights, skimmers/weir doors, ladders, steps, auto fill valves, drains, etc. are all common hiding spots). Those areas can hide algae that is not easily brushed and form a protective later that helps protect it from the elevated chlorine.
For your other question Ammonia, read up here. Generally, your CYA will be 0 because it gets consumed. Have you done a CYA test recently?
Ammonia - Further Reading
www.troublefreepool.com
- Jun 7, 2017
- 10,021
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
The water would not maintain any chlorine level for more than 15-20 minutes. And his CYA measured 0. It was discussed at length on this forum by me (I discovered and remediated it for him), but I cannot find it at the moment. It took around 50 gallons of chlorine to neutralize the ammonia.
Thanks for the info. Yes I have done a CYA test this week and it is roughly 40 although I agree with Newdude above that the Taylor CYA test is not the easiest to interpret.Sure it is. FC of 9-11 doesnt work for your pool in its current state, so your demand for chlorine is higher than that, unfortunately.
If I had to bet, it would be hidden algae somewhere (behind lights, skimmers/weir doors, ladders, steps, auto fill valves, drains, etc. are all common hiding spots). Those areas can hide algae that is not easily brushed and form a protective later that helps protect it from the elevated chlorine.
For your other question Ammonia, read up here. Generally, your CYA will be 0 because it gets consumed. Have you done a CYA test recently?
Ammonia - Further Reading
- Jun 7, 2017
- 10,021
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
Can you post a full set of tests including water temp?
I just brought FC up to over 16 (SLAM).
CYA = 40
pH was 7.4 before raising the FC level but still a possibly questionable number with the FC level at 9 ppm or higher
TA = 60
Phosphates = 3400
Water Temp = 68 F
CYA = 40
pH was 7.4 before raising the FC level but still a possibly questionable number with the FC level at 9 ppm or higher
TA = 60
Phosphates = 3400
Water Temp = 68 F
This is 24 hours after a complete brushing of the pool. It actually seems to be growing much faster than before the previous SLAM.
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- Jun 1, 2018
- 16,159
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Oh that’s certainly algae!
The ph reading is fine up to 10ppm so you’re good
How confident are you in your cya reading?
Be sure to bring the sample to room temp as cold water can throw it off.
If between two values always round up for chlorination purposes.
- Jun 1, 2018
- 16,159
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Another thought…
Have you cleaned out your polaris? Like checked its guts & hoses?
They float on the water often only 1/2 full & some have reported algae in them periodically.
Also, if you have an auto fill pot check that out
Have you cleaned out your polaris? Like checked its guts & hoses?
They float on the water often only 1/2 full & some have reported algae in them periodically.
Also, if you have an auto fill pot check that out
How are you getting phosphate measurement? Make sure you don’t mix pool store test results with your own test kit results cause that’s almost guaranteed a problem.
Was this picture taken after you had reached SLAM level of 16ppm and held for 24 hrs? Based on your earlier posts - you are following the SLAM process however, I looked at your Pool Math logs but they have not been updated. I was hoping to see if you had been testing every 3-4 hours to bring FC back up to 16ppm. With algae in the pool your FC level will decline over some length of time and it is important to raise it again - the MAINTAIN part of SLAM process.
You mentioned a solar cover but assume that is not on the pool while you are doing a SLAM. Put it on your driveway and clean the underside well with a chlorine mixture to remove any algae that may have been trapped.
Keep us updated and we will keep throwing out ideas to help resolve the recurring algae issue. Good luck.
That looks like it is mustard algae.
Mustard is very resistant to chlorine and it takes more to kill it and more to keep it from coming back.
Mustard is very resistant to chlorine and it takes more to kill it and more to keep it from coming back.
- Mar 5, 2020
- 3,221
- Pool Size
- 66000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V35
I think James may be into something there.
Treating for mustard algae is a two step process. First a normal SLAM, followed by 24h at mustard algae level. And after that you might have to keep FC elevated for a while.
www.troublefreepool.com
Treating for mustard algae is a two step process. First a normal SLAM, followed by 24h at mustard algae level. And after that you might have to keep FC elevated for a while.
Mustard Algae
Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.
www.troublefreepool.com