Stubborn mustard algae

[fsoliday]

Hello all new to the forum. Here's what's been going on with my pool.... We've been in our house 7 summers now. First few summers with pool were ok. About 4 years ago got stubborn yellow/greenish algae all over the pool surface that was very difficult to vac / sweep off the sides. We got this issue 2 years in a row in August. The following year I was convinced I had a hole in the liner because I thought there was sand all over the bottom. Last year after much research I figured it must be mustard algae... Tufts of brownish "poofs" all over the bottom of the pool. They return the following day despite vacuuming. Apparently, per my local pool store, this isn't very common in PA. I followed their directions, slammed the pool chlorine levels off the charts, threw all equipment in pool and soaked it. Then treated with knockout. This seemed to do the trick until the end of summer, it returned & I repeated the process. Needless to say it's back. Every two days I'm vacuuming. Water is clear otherwise. I've aggressively scrubbed walls, shocked, treated with appropriate algaecide & cleaned my cartridges. We just got a new solar cover this year & Saturday was the first we put it on, it's a necessity as the pool temperature is miserable without.
I really just need a solution to limp through this year. We are in need of a new liner & plan on getting one next year. With that I plan on throwing out & getting new anything I can - cartridges, toys, etc. planning on slamming pool before closure to try and eliminate what's in the system.
I need to get a better test kit, just using digital test strips now. Ph was 7.2. Alk was 182. Chlorine was unmeasurable (high). To note what my strips say and what the test at the pool store reads is usually markedly different in regards to ph and alk. My "stabilizer" level was adequate when I opened the pool.
Also of note I've been vacuuming water to "waste" so it's not running through cartridges. Waiting for new pool max vac to come via fed ex.
Sorry for the lengthy post. I work 2 12s in the next 2 days so I apologize if I don't respond quickly. Will post a pic of the "mustard" algae when I can

 

[fsoliday]

Post vac

 

[Texas Splash]

Welcome to TFP! We can certainly help you. You are already motivated about our first concern - getting the proper test kit. Many of us use the TF-100 (linked below) but you can chose for yourself at that same link. The other major factor - pool stores and their advice. A big "no-no". YOU are not their #1 concern. Their products generally do not resolve your issues either.
So here's what you should do ... First, look at the test kit link in my signature and get one ordered right away so that YOU are in control. Everything goes from there. When you are experiencing algae, it needs to be SLAMmed the TFP way - not the pool store way. Please check-out the other links below as they are absolutely critical to help you understand the process. It's not hard, just takes a little involvement and you'll be surprised of the results.
In preparation for SLAM, also know and understand the Chlorine/CYA chart. You'll be using it when your kit gets in. In the meantime, start shopping around for your next most popular pool ingredient - regular liquid bleach. You will use a fair amount of it during the SLAM.
This may seem like a lot of info, so I'll slow down for now, just get the kit on order and we can help you more from there. Glad you joined us!

 

[duraleigh]

Your description fits a low chlorine pool exactly. Greenish-brownish-yellowish dust that "poofs" when you touch it and it reappears every day even if you clean it.

You have both living algae and some chlorine, but not enough chlorine. The (invisible) living algae is killed partially and settles to the pool floor. Because you don't kill all of it, it grows back again and you kill it again and it's a never ending cycle.

If you have faith in what we teach and stay OUT OF THE POOL STORE, you can SLAM your pool successfully and have crystal clear water the rest of the summer.

 

[tim5055]

I think Dave hit the nail on the head.

What you are calling "SLAMMING" isn't what we call SLAMing at all. A SLAM is not a one time, or even a multiple application of "slammed the pool chlorine levels off the charts" as you put it. It is a scientific application of a specific amount of chlorine for however long it takes to prove that everything in the pool water is dead. The shortest SLAM takes days of testing the chlorine level and adding more to maintain the assigned shock value for your level of CYA in the water. During a SLAM most people test and adjust the chlorine level in the water four or five times a day (the minimum is two, but that makes the SLAM last longer.


So, order a TF100 and at least include the XL option. That will give you what you need while you are clearing the pool, and probably enough reagents for a couple of years normal use.

Then read the directions on SLAMing your pool in the How To section of Pool School and follow that procedure completely to the end.

* CC is 0.5 or lower;
* You pass an OCLT (ie overnight FC loss test shows a loss of 1.0 ppm or less);
* The water is clear.

When all three are true, you are done SLAMing and can allow the FC to drift down to normal levels.

You will note that during the SLAM we don't add any of the things the pool store has been selling you like Knockout & algecide. Chlorine, that is what will fix your pool.

 

[fsoliday]

Test kit is ordered. Will post a picture of what I assume to be mustard algae as soon as it's back... Which is almost immediately. Will post test results as soon as I get kit in the mail, or potentially soon if I can just get an "in the meantime, while I'm waiting test at the pool store". At best that'd be Thursday. Appreciate the help, feedback & comments.

 

[duraleigh]

If you want to do something helpful to your pool, you can put in a small jug of bleach each evening until the kit arrives. For sure, DO NOT use any more pool store chemistry.....it is only a distraction to the task at hand.

If you post pool store test results, not many of us will pay much attention to them.....we have learned how untrustworthy they are. What will really start the ball rolling is when you post the results that YOU get from your own kit. No one cares more about your pool than you do and the kit will arem you with the precision you need. Reading and asking questions will get you the knowledge that you need and you'll end up with a great looking pool.....promise!

 

[tim5055]

Test kit is ordered. Will post a picture of what I assume to be mustard algae as soon as it's back... Which is almost immediately. Will post test results as soon as I get kit in the mail, or potentially soon if I can just get an "in the meantime, while I'm waiting test at the pool store". At best that'd be Thursday. Appreciate the help, feedback & comments.

Great, we look forward to to your own test results. I truly believe you have just plain run of the mill algae, not mustard. The description just isn't meshing for mustard, but the solution for both is essentially the same - chlorine.

 

[fsoliday]

So I got my test kit today & here are the results:
FC 21 ppm (yes 21)
CC 0.5
TC 21.5
calcium hardness 375 ppm
TA 100
cya 100
ph 7-7.2 ish

so 2 questions & I will attach pictures
1. Took 10 drops for TA test to turn hot pink, am I to be looking for a deeper red
2. Which tests should I be using the magnetic stir stick for

 

[tim5055]

For the TA & CH tests you are looking for a color shift. Just keep adding drops until the is no longer any change. The last drop,that caused no change is not counted.

I use the Speed Stir for FC, TA & CH

The problem I see is that 100 is the limit of the CYA test. So, you don't really know if it is 100 or some number well above that. I would recommend a 33% water replacement to get it down to the level you can test.

 

[fsoliday]

Sorry for all the duplicate pictures, new at this forum
can't seem to get the better of the "algae"
pictures up
As far as my FC of 21, shocked mid last week with 3lbs of granulated shock as I had a level of nearly 0. My Chlorinator is set to 2-3
"lucky" for me I have a leak somewhere in or around my filter, losing about 1/4-1/2 inch of water a day and have had to replace..... Which from my from my reading is the best way to lower cya

 

[fsoliday]

I want my pool to be as good as it can be, but we are 100% planning on replacing our liner next year (holds water but i have several patches & there is settling and divits one one side that are considerably stretchy and weaker this year). With that taken into consideration is it worth it to do a 33% drain this year?

 

[tim5055]

As long as you continue to use the powered shock and tabs in the inline chlorinator you are never going to get control,of the pool. The tabs and shock are almost half CYA so the more you use them the more CYA you add which means you need more chlorine to keep the algae at bay. It's a vicious cycle. You have to break it by using liquid chlorine.

 

[fsoliday]

Are you recommending using purely over the counter bleach and that alone? No "shock" no chlorine tabs?
Just trying to understand
Thank you for your input and feedback


Sent from my iPad using Tapatalk

 

[tim5055]

Are you recommending using purely over the counter bleach and that alone? No "shock" no chlorine tabs?
Just trying to understand
Thank you for your input and feedback


Sent from my iPad using Tapatalk

yes, that is exactly what we teach. If you don't have a Salt Water Chlorine Generator, liquid chlorine is the way to go.

Read this :

Pool School - How to Chlorinate Your Pool

 

[DaninFLA]

you really need to figure out your CYA first. test limit is 100, so if you tested it as 100, it could be 100 or it could be 900 no way to know. try a dilution. mix pool water with tap water at at 50/50 ratio and then use that to fill the CYA thing to the bottom of the label, then add your reagent and test per instructions. if your CYA test at 60, then you have 120. if it tests at 100, well then that's gonna suck with the list of chemicals you use, I suspect its going to be very high

if you are planning on replacing the liner next year, you may want to consider trying to bumping that up to now and doing a full refill and start from scratch.