I recently posted about my SWG failure and how I was having to slam my pool for the first time. In reading about mustard algae I got concerned because I have noticed brown stuff off and on especially where the steps meet the wall but I got the impression it wasn't that common and my pool is in full sun most of the day. Anyway I finished the slamming process and installed the new SWG setting it on 20% as the old one had been After 2 days The fc was only 5 so I upped it to 40%. Today the fc was only at 3.5 and with goggles I could see brown spots pretty much all over the pool bottom. I feel sure now that it is that dreaded mustard algae. It is fiberglass pool and I have to admit I am not good at brushing as I am a youthful but not too strong 60 something woman so I am thinking I may just have to call a pool service but know they will want to follow pool store procedures and I am a TFP follower. I am worried about new SWG I upped it to 80 % after seeing that this evening but know I have to do something quick. Could use some guidance please.
Mustard algae
- Thread starter Sharlotte
- Start date
Give us some recent test results. Are you keeping FC above minimum at all times? Will the pool pass an Overnight Chlorine Loss Test? More here on mustard algae, Pool School - Mustard Algae
This afternoon the FC was 3.5 and PH 8 that is all I tested today. I did the slamming and it took quite a while, 6 or 7 days but I did pass the tests CC 0 clear sparkling water and overnight drop of less than 1. The chlorine dropped rather quickly though, I thought it might take longer but it was back down to 7 in 2 days, I thought maybe because it is so hot. When it reached 7 I installed new swg. Everything was within normal limits. That was 4 days ago. testing after 2 days FC was 5 and Ph 7.8 so I bumped up the swg and added acid, everything else normal. However after I finally finished the slam I was reading where someone said do the CYA test outside and I had been doing it indoors so I did it outside and it was 80 and I had slammed for 60. I thought maybe that was why it took so long to get through the process but maybe not. I am leaving town for 2 weeks next monday. I am wondering perhaps I should go with the pool store remedy to try to get rid of it then just vac out to the outside add new water and repeat until CYA is back down then soak filters in bleach solution? Or do I need new filters? These are not very old, I think 1 season and still clean up nicely. I will do complete testing in the morning and post results. I sure hate to even think of pool store remedy but the thought of the slamming again so soon, and I cleared the shelves of 2 local stores of bleach, not sure they have restocked (just kidding) I don't know how long the swg was not working before I realized it but I usually only test once a week because I am the only swimmer and there are no trees over it. It doesn't get dirty much unless it storms. I use bleach in the winter and shut the swg down because I put a vinyl dome over it to swim year round. When I took the dome off and turned swg on it was working at first then just stopped. I also really need to get back to swimming everyday especially before this trip, I missed a week during the slam and without it my arthritis makes my life miserable.
I read the pool school mustard algae article again and it refreshed my memory as to why I didn't think I had it before. Because it is not on the sides, just the bottom. But I don't think there would be pollen to this degree this time of year and while I was swimming I put a yellow cover over the light and when I did some orange clumps (small) seemed to come out of the light fixture like the cover scraped it off. Also this time it is all over the pool floor not just a few areas. But it isn't really visible unless you get in with goggles and look
It is safe to swim with up to shock level.
Your FC is too low for your CYA, [FC/CYA][/FC/CYA], it needs to be above minimum at all times to keep the pool sanitized.
Do an Overnight Chlorine Loss Test to see if there is algae again.
More here on how to clean cartridge filters, Pool School - Maintenance and Cleaning of Pool Filters
Your FC is too low for your CYA, [FC/CYA][/FC/CYA], it needs to be above minimum at all times to keep the pool sanitized.
Do an Overnight Chlorine Loss Test to see if there is algae again.
More here on how to clean cartridge filters, Pool School - Maintenance and Cleaning of Pool Filters
i know its too low thats why i keep bumping up the new swg. My old one kept it up on 20% so thats where i started after 2days i bumped it to 60 and today i bumped it to 80 its not keeping up, another reason i suspect mustard algae
It is best to bump FC above target using bleach and then work on the SWG settings to make adjustments. That way if FC drops it stays at target.
If its mustard my FC was well above my target and it still came back. So far I've had luck keeping my FC at 'Mustard Minimum' and using PolyQuat 60. I say so far b/c I just get the feeling it's waiting to catch me asleep at the wheel; so many relapses of mustard on so many forums. Its seems like once you get it its like managing a disease or something. Never really ever TRULY 'goes away'. I'm sure there is some pool tool or SOMETHING I didn't bleach/clean that will reintroduce it. Plus I got it naturally the first time, so what's to say whatever introduced it prior isn't going to do it again?
I really despise mustard algae.
http://www.troublefreepool.com/threads/2177-Chlorine-CYA-Chart
I really despise mustard algae.
http://www.troublefreepool.com/threads/2177-Chlorine-CYA-Chart
Allright this mornings readings are FC 4 CC 0 PH 7.5 Alk 60 CH 300 CYA 60 I have a question about the CYA As I am looking in and putting stuff in, the spot goes away at 80 but as it settles I can still see it. It doesn't completely go away and stay gone until 60 so is my reading 60? Pooldv I believe I have 2 and a half gallons of 8.25% bleach left from the slam. I will go pour it in as soon as the lightning passes. I put the swg on 80% last night and really expected it to be above 4. My thinking is it has to be algae keeping the fc eaten up but it occured to me just this morning perhaps I purchased a faulty SWG?? Could that be?
Here are some reference pics of the CYA test, https://www.taylortechnologies.com/ChemistryTopicsCM.ASP?ContentID=44
Most likely algae is consuming FC AS fast as the SWG is producing it. You can perform an Overnight Chlorine Loss Test to confirm if there is algae growing.
Most likely algae is consuming FC AS fast as the SWG is producing it. You can perform an Overnight Chlorine Loss Test to confirm if there is algae growing.
Thank you so much for that link! That makes all the difference in knowing how to read that test, I'd say the CYA is about 70 then.
I did the overnight test every night of the slam but I had not replaced the SWG as yet. Should I turn it off when I take the reading so it won't add any? It seems that would mess up the test.
I added the 2 1/2 gallons, I have a quilting class at 10 will have to check to see what it did later on.
You should have your SWG off for an hour or so before you take your evening OCLT test, and all through the night. Before the sun hits the water, take your follow up test.
Yes, step 1 of the Overnight Chlorine Loss Test instructures say to turn off the SWG.
Well maybe I am crazy or have a bad swg or maybe it just needed some help but I'm really confused. Yesterday after bumbing it up to 80% the night before FC had only gone from 3.5 to 4. I put in the 2 1/2 gallons of bleach left from my slam and last night just after the sun went down FC was 14, this morning FC is 13. So it would seem the brown stuff isn't algae? Should I turn swg back on now while its still higher than normal? When I started using TFP a couple of years ago I wrote my desired FC was 3-5 now it seems I'm reading that it is 7. Not sure how I came up with such different numbers.
After I posted this I went back to look at charts again and see the difference is because I use a swg and my cya is 70 so 3-5 FC is correct for me I assume. If in fact like someone said earlier that is not high enough please let me know.
Just a thought I'd like to toss out there...I have never seen or heard of a pool service that follows the TFP method. Probably because most are associated with a pool store I guess but I was just wondering if perhaps there are some out there and if so any in the Tulsa Ok area? I would love to have someone to take care of my pool as I am getting older but I really don't want the pool store products used.
Yes, 3 is the minimum and 5 is the target. [FC/CYA][/FC/CYA] Meaning that FC should never drop below 3. I would target 5 or 6 and make sure it is 4 when the SWG turns back on.
With an SWG you will do better with a pool service because they won't be chlorinating with pucks or dry chlorine products.
With an SWG you will do better with a pool service because they won't be chlorinating with pucks or dry chlorine products.
I'm sorry I guess I am very confusing because I use the swg only in the summer and most of the year from about the end of September until about the end of May I have a vinyl dome over it and I use only bleach and dry acid mainly I change due to the swg seems to run the ph up all the time so it's a constant battle to keep it down. I get in my own little head and I forget that when I'm talking to the forum that everybody doesn't know I use both methods. I had a pool service in the beginning and after just a few months the heater went out. The man who installed the pool told me it was chemical damage to the heater and it wasn't covered under warrenty So I was out the cost of a new heater. Been taking care of it myself ever since out of fear I guess...
I turned the swg back on this morning but dropped it to 60% FC is now 12 but it was only 13 this morning and it's been hot and sunny. Is that about a normal drop for a sunny day? Should I turn it back off until it drops lower or just lower the percentage it's set on?
Yes, I do the same thing. When the water temp drops below 70 degrees I switch to bleach.
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