Quick mustard algae question

belle4397

Member
May 16, 2020
12
Chickamauga, GA
Relatively new pool owner.... After weeks of confusion (algae developed... Tried ro SLAM twice, then maintained perfectly balanced water, just to have it come back over and over) I am 99% sure we have mustard algae.

I have read the recommendations, which say to raise FC and THEN scrub everything. Since a lot of the stuff that needs scrubbing requires getting in the pool, would it be sufficient to scrub before adding chlorine? Not sure I want to swim in 20+ ppm chlorine. Lol

Or at least scrub the ladder and light before upping the chlorine? I just want to make sure we do this right the first time around.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
21,204
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
You need to brush, not scrub, stuff while it is soaking in the high FC level. Brushing breaks the biofilm protecting the algae and allows the chlorine to attack it.

What type of pool do you have?

What do you need to get into the pool to scrub?

From ...


While at mustard algae shock level you need to throughly brush the entire pool, including walls, floor, steps, skimmer, under ladders, everywhere. All pool tools and toys and anything else that is used in the pool needs to be wiped down with a dilute bleach solution or soaked in the pool for an hour while at mustard algae shock level. Bathing suits should be run through the laundry. If you have underwater lights, they should be removed from their niche and the niche brushed out, and then the lights replaced. If you have fountains, or waterfalls, or other water features, they need to be run for at least an hour while at mustard algae shock level. Be very thorough, or you will most likely just need to do it all over again.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
21,204
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
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Pull out your light from the niche onto your deck before you raise the FC to mustard algae levels. Then you can scrub it and float it in the pool water.
 
Last edited:

belle4397

Member
May 16, 2020
12
Chickamauga, GA
Sorry, I thought I had already created a signature. Since my phone normally doesn't display them, I didn't realize it was missing 😬

Not sure why it didn't occur to me that I could remove the light before scrubbing it! I guess we'll just do the best we can with the ladder. Thanks for the help!
 

red-beard

Gold Supporter
May 27, 2019
632
Houston, TX
What is your CYA level? I had Mustard algae issues for years. I finally drained and refilled my pool and kept the CYA on the lower side (30 ppm) and kept the FC on the high side (8 ppm) after doing the SLAM.
 

belle4397

Member
May 16, 2020
12
Chickamauga, GA
What is your CYA level? I had Mustard algae issues for years. I finally drained and refilled my pool and kept the CYA on the lower side (30 ppm) and kept the FC on the high side (8 ppm) after doing the SLAM.
That's funny, because last year when we bought the house, we were clueless. We were using the trichlor tablets, so our stabilizer got super high before we realized what was going on. We didn't have any issues with any type of algae though until this year where we've gotten our CYA down to normal levels (currently it's 40).