Can't get rid of mustard algea

#1
I began the season with a green pool, it's all clear now, but I think I still have mustard algae which I"ve had since last season but never completely got rid of. It looks like there is dirt on the bottom and sides of my pool, when I sweep it it looks like a puff of smoke, the water gets slightly cloudy then it settles again on the bottom of the pool. I have kept the FC up but it's still there. I'm using granular chlorine from wal-mart as I am a newbie and I already had it before I began reading this forum and gained knowledge from all of you. I plan on getting bleach when I run out. My test kit is not in yet either, so I don't know my exact numbers, it is ordered and should be here any day now. Just want to get rid of the stuff already!! Any suggestions.

Thanks!
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
31,333
Sebring, Florida
#2
Rather than guess at the issues, I think your pool will get cleared more quickly if we all wait for your test results.

It's hard to tell you which direction to take when no one is sure where you are.

Mustard algae is reasonably rare but is frequently mistaken as a problem in many pools.

While your waiting on the kit, see if you can google some pictures and descriptions for mustard algae. It may be that you've got remnants of green algae hangin' around as dead algae.....it's not always green.
 

grangerhj

Active member
Oct 1, 2007
39
Lafayette, La
#3
I am uncertain whether I have a mustard algae myself- same dusty looking bottom and sides of pool. this am readings were TC-4
CC-0
alk-100
ph 7.4
calcium 180
cya-50

temp 82
15,000 gal fiberglas pool

About 14 days ago I used Vit C and metal out for metal stains I also added Polyquat 60 when I treated because i dropped TC to 1 - I began adding bleach 24 hrs later (stain all gone) adding it slowly for the next week never getting above 3 ppm. This weekend the water looks a little cloudy but my readings appear OK Took water to pool store this am and they verified the reading I have been getting. They recommended using a water clarifier but I did not- can I have mustard algae or any algae without showing any CC? What would you do?
 

edbson

Well-known member
Jun 25, 2007
72
#4
Are you sure it isn't just "dead" algae? when I have dead algae it always does that puffy cloud thing./ Vacuuming very very slowly usually takes care of the problem.

The granular chlorine from walmart has CYA in it, it is the same as Trichlor. Be careful with it, or you will end up draining your pool.
 

grangerhj

Active member
Oct 1, 2007
39
Lafayette, La
#5
Thank you edbson- I vaccumed yesterday and it is back to being dusty today. I only use bleach now- I had a horrible CYA problem 2 years ago. I am glad you mentioned the granular chlorine from Walmart because my husband had looked at that- will tell him it is a no-no. Does anyone know if I can have an algae problem with a 0 CC reading?
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
31,333
Sebring, Florida
#6
edbson speaks true words of wisdom!! :lol: :lol:

I would add to that to bring your FC up to about 20ppm, brush the sides of your pool, vacuum. hold that FC at 20ppm by testing and re-adding for a couple of days or so and I'll bet that'll all go away.

Yes, you can have algae with little or no CC's. That's fooled me more than once but it can work that way.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#7
Mustard algae can do everything you describe and so can very fine dust, pollen, or algae that is right on the edge of growing and being killed off just as quickly. Dust can stay in suspension for days, slowly settling out to the bottom a little each day. I get that every time there is a significant wind blowing stuff into the pool.

You can have algae without any CC.
 
#8
Got my test kit!!

I received my test kit today, here are my numbers
FC-41
CC-.5
TC 41.5
PH-7.2
TA-110
CH-130
CYA-80

I have no idea what these numbers mean but think they may be good please advise.
Thanks,
Lanice
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#9
Your numbers look good for a vinyl pool, plaster would need more CH. If it is mustard algae you are doing the right thing to fight it, very high FC levels and brushing. Keep the FC level up above 40 for 24 hours after the FC level holds overnight and that should take care of it. Mustard algae can be very persistent and reappear over and over if you aren't very through with brushing and high FC levels.

When you say "on the sides" does that mean that it is appearing on vertical surfaces, or only on sloped surfaces? Vertical surfaces would mean mustard algae for sure. If it is only appearing on sloped sides, then there is a chance that it might be pollen.

For details on what the various test results mean try the What to test for and what the tests mean sticky.

It would be great if you could post some basic specs for your pool and equipment in your signature. That will make it simpler for us to answer your questions completely.
 
#10
I have updated my signature to include the specs on my pool. I brushed again this afternoon and really took a look at the stuff on the bottom and sides of my pool, it is only on the sloped sides of the deep end and bottom of the pool. It is not on the vertical sides in the shallow end. I have kept my chlorine high for some time now, about a week. If this is mustard algae shouldn't it have been gone by now? Thanks again for all the help. I feel I have some power now over my pool where as before it had the power over me.

Lanice
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
31,333
Sebring, Florida
#11
Lanice,

Test for FC again tomorrow morning and post that number. That'll be helpful.

What are you using to chlorinate?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#12
I think it is pollen. Mustard algae usually vanishes at the first sign of shock levels of chlorine, only to reappear when the chlorine level goes down. Pollen can look and behave almost identically if you don't have a microscope and pollen remains even at high FC levels.