Help for Those Who Cannot Defeat Algae with the Desired Method


Well-known member
May 17, 2016
Lancaster, Pennsylvania
I think most will agree that this is a definite agree to disagree topic on TFP. But here it goes.....There are some members who, for whatever reason, use TFP method for getting rid of mustard algae (the dreaded "it could be pollen, dirt, or sand") but it constantly reappears. I will up front admit to being one of those members. I have certain fixtures that I cannot thoroughly brush. I spent from May 8, 2019 to the end of July doing everything the book. It was a battle I could not win. So I reluctantly researched elsewhere and finally came up with something that works for me. I think it would be nice to have somewhere in the forums for us to go and get advice or share what has worked or not worked for us. We wouldn't have become members if we didn't want to be full fledged TFP, but as with everything, there is always an exception that takes people outside of the box.


Bronze Supporter
This comm is very welcoming and open-minded, I don't see why just posting on the appropriate forum wouldn't be acceptable. I don't think there's really a need for an alternative methods forum. In your case, just post what worked for you under the Algae forum.

I'd be interested to see this method!


Well-known member
May 17, 2016
Lancaster, Pennsylvania
Hi Maddie!

Okay....this is the only thing that has worked for me so far.

Before I started my treatment, I manually vacuumed the pool; cleaned the filter; and cleaned the salt cell. I made sure my pH was 7.2, TA was within range, CYA at 45, CH min of 200, salt level appropriate for my SWG, and the FC was at shock level for my CYA using Pool Math.

I added chlorine to bring the FC up, waited at least 4 hours and tested the FC level. I wrote that down to keep as a reference for the pre-treatment FC level.

Then I brushed the whole pool thoroughly with a lot of force on the brush. Next, I turned off the SWG and set my VS pump to 2750 RPM (and left it at that speed for 24 hours straight). After brushing, turning off the SWG, and setting the pump speed, I added 6 oz of Yellow Treat (88% NaBr) to my 39,500-gallon pool (small amount for pool size), scattering it over as much of the pool as possible. Then I followed that with 2 gallons of 10% liquid chlorine. I put all pool equipment (brushes, nets, hoses, vac stuff, etc.) in the shallow end of the pool. I emptied out the vac hose and filled it with the treated water and left it in the pool.

On day 2, I checked the FC and added another 2 gallons of liquid chlorine and brushed the whole pool. I turned the SWG back on at 80%. I noticed my SWG's avg salt reading went up once the NaBr circulated. For the next 4 days, I brushed like crazy and kept checking the FC level (I kept adding enough liquid chlorine to maintain the pre-treatment shock level). I made sure I thoroughly brushed in the AM and PM every day. During the rest of each day, I brushed any algae I saw; the skimmers; the steps;, and the seams.

For me, on day 5 everything looked great....normal! So, I decided to shut off the SWG that night to gauge the FC. I took a reading then and did a reading early next AM before turning the SWG back on. There was no FC loss.

I also put 2 Aquafinesse tabs in 2 skimmers (for a total of 4).

I just added the 2.5 oz maintenance dose with 1 gallon of 10% liquid chlorine and another 4 Aquafinesse tabs (2 in deep end skimmer and 2 in one of the shallow end skimmers).

In the future, I will just add 2 tabs total to the skimmers each week and 2.5 oz NaBr every 1.5 to 2 weeks.

I fought this stuff from May 8th to the end of July last year because I wanted to get rid of it using the SLAM process. I kept the FC at 60% of CYA and brushed the pool thoroughly more often every day than I did during the 4 days for this treatment. I ended up using BioGaurd Banish, Aquafinesse tabs, and then PolyQuat 60. That got the pool to where the family could finally swim in August…but it still wasn’t ideal. I have a long thread in the forum.

The pool steps have crevices that are impossible to thoroughly brush, and the fiber optic lights can only be cleaned if the liner is changed ☹ So, they are more than likely a source of reappearance. It has places to hide in my pool...ugh.

This current approach has made the pool look and feel like it always used to 😊

There used to be constant reappearance of the sediment (mustard algae) and dust clouds. Now, the only thing I see is the 2 tiny weak looking spots on the deep end corner around week 3 (if I don’t do the maintenance dose).



TFP Expert
Platinum Supporter
May 23, 2015
Tucson, AZ
You’re converting your pool into a bromine pool. Bromine is known to kill mustard algae faster than chlorine. The downside is bromine cannot be stabilized against UV loss and so it will constantly use up your free chlorine. When you add bromide (Br-) to your water, chlorine oxidizes it into sanitizing bromine (Br+). Then the sanitizing bromine sanitizes or oxidizes something and is converted back into bromide. The cycle repeats until all the chlorine is consumed. UV destroys bromine just as it does chlorine but with one difference - chlorine can be protected by CYA whereas bromine can not. So, adding bromide to your water simply adds a fast sanitizer. At a high enough level, your bromine will rapidly exhaust your chlorine supply and your water will become unsanitary allowing algae to grow again. You’re creating a yo-yo effect which will only get worse over time, not better.

Now, the SWG can play a role here as it will create a constant stream of bromine as it runs. So, if it’s operating properly, you might be able to keep a consistent bromine level in your pool. But it too will have to be run far harder than normal to keep up with UV loss.

All those other chemicals (aquafinese, etc) are simply acting as surfactants, clarifier and detergents that help to keep biofilms from forming.

It’s your pool and you need to do what you think is best for it, but a bromine pool is not something TFP would ever endorse people doing. It’s simply much harder to work with and more expensive in the long run. I realize the SLAM method didn’t work for you, but that’s really a minority situation. Most pool owners, even those that get mustard algae, find success with the SLAM methods taught here.


Well-known member
May 17, 2016
Lancaster, Pennsylvania
Hi Matt

I held off on using this method due to being aware of how the NaBr works.

Unfortunately, there are places that I cannot physically get to in the pool in order to brush.....which complicates the process for me.

I am only using 1/4 the dose recommended of the 88% NaBr for my size of pool. Also, I don't add the maintenance dose as often as they recommend.

...a bromine pool is not something TFP would ever endorse people doing. It’s simply much harder to work with and more expensive in the long run. I realize the SLAM method didn’t work for you, but that’s really a minority situation. Most pool owners, even those that get mustard algae, find success with the SLAM methods taught here.

I understand and this is why I didn't feel what has been working for me should be posted in the algae prevention and treatment forum.

However, there is a small number of us who have spent a lot of time and money trying to get rid of this crazy stuff using TFP and found we desired advice from forum members on alternate methods. Each one of us diligently utilized the TFP approach for a month or more. We greatly appreciate having this forum.

At this point, I'm just happy that the family has been able to swim this season :)


TFP Expert
LifeTime Supporter
Jun 12, 2009
NW Ohio
I have a lot of comments on your situation and solution, but I'm just going to speak to the topic of the thread.

TFP is about teaching Trouble Free Pool Care and the methods and theories involved in it. Suggesting having a place for the promoting of methods specifically discouraged by TFP would be like suggesting a vegan forum have a "Meat Lovers" section. TFP is not a general pool care website any more than a vegan forum is a general food website. If such a forum were implemented it would be nothing but us correcting bad chemistry ideas and challenging these things every step of the way.

Lorri is right that TFP is open minded, but I think she misunderstands what that means. We have our set of techniques and ideas, but we are open to those ideas being challenged with well thought out reasoning and data. For instance, we once suggested that CYA didn't register until week after adding it, but after good observation and testing found out that this isn't true and restructured our advice. What being open minded does not mean is accepting any idea with open arms. This specific area of the site is full of people with their ideas that have been shot down, harshly in some instances. Saying "this worked for me" is not good enough, if someone doesn't understand why it worked and can explain the side effects and offer reasons why it is a good option over TFP and despite the drawbacks, then IMO they are no better than a pool store employee just doing what the chemical companies tell them to do. Open mindedness means we welcome new data, not testimonials.

Best of luck with your pool.


Well-known member
May 17, 2016
Lancaster, Pennsylvania
Hi Matt

I was tired when I responded and I realized it might help if I clarify what I did in an attempt to prevent the yo yo effect (even though the dose was small for my size of pool).

Btw...the reason I keep using the Aquafinesse is due to its effect on biofilm. seems to have helped kill any spiders (especially wolf) that make it into my pool. It used to be such a problem that kids didn't want to swim in it (prior to mustard algae issue).

Added info: What I use in the pool is salt, liquid stabilizer, muriatic acid, baking soda (rarely), the Aquafinesse tabs, 10% liquid chlorine for an occasional shock Tx and when treating algae, 88% NaBr (already explained), and if CH is below 200 I use Cal Hypo 73% when I want to shock.

Before starting to use the NaBr, I did make sure my FC level was at Pool Math shock level and that the pH started off low (7.2) and TA was stable at 90 (works best for my pool).

Instead of adding 20 oz NaBr and 4 gallons of 10% chlorine, I added 6 oz of NaBr and 2 gallons of the chlorine.

Then, the next day I add the same amount of 10% chlorine to keep the cycle going without dipping into the pre-treatment FC amount.

The 3rd through 4th day I tested FC like I would have for a SLAM. I decided to look at any drop in FC to be due to the effects of the NaBr and made up my mind to add liquid chlorine to bring the level back up to the pre-determined shock level.

On the 3rd day, there was only a few light grayish white patches reappearing (and not as frequent) and sparse gray dust clouds when brushing the slant.

On the 4th day, there were no dust clouds and there was only 2 small spots that appeared (only once) in the corner and their appearance was like I had never seen before (the sediment appearance had changed to what looked like a whitish fluff?!). I focused heavily on that area that whole day.

Day 5 had no dust clouds and no signs of the algae. So... that night, around 8 PM I tested the water and made sure my FC was at or near shock level and shut off the SWG.

Day 6 around 7 AM, I tested the FC level and there was no FC loss and CC continued to be zero (which is what it was even before I started the process), I then turned the SWG back on.

Side note - my salt avg reading on the SWG increased on day 2 ( I don't rely on it but it has been consistent so I thought I would monitor it throughout the next few weeks).

From Day 6 onward, I chose to brush every other day, check FC in AM and PM, and not add any more NaBr. I wanted to see how long it stuck around.

What has me stumped is......My overnight test from day 5 onward showed no FC loss, but the salt level remained constant (at day 2 value), and there were no signs of algae. Then around day 18, that small amount of algae reappeared in the deep slant corner and the salt level dropped back down to pre-treatment level. Does that mean the NaBr was no longer around at day 5 or day 18 (which would be more realistic). Per one of ChemGeek's posts from the past, the NaBr does eventually deteriorate due the sun and no longer impacts the available chlorine.

I appreciate the conversation concerning this and hope everyone realizes the reason I put this in this forum was to generate discussion concerning the topic without swaying others who may have just begun having issues with this algae and may have success with TFP method :)



LifeTime Supporter
May 8, 2012
Southeast Michigan
I've been watching this thread because I find it interesting.
Aquafinesse according to the MSDS sheet is Sodium Carbonate. Which makes sense it would work because it is the same thing as: Soda Ash, washing soda, Arm & Hammer Super Washing soda. Other brands call it: Balance Pak 200, pH Increaser, etc. TFP recommends using the first 3 which are the cheapest and easiest to find. Aquafinesse is expensive.
Last edited: