It has some serious chlorine resistance, and does not just die off and disappear even with a hard shock. Leaves brown stains EVERYWHERE that have to be hard scrubbed off with a wire brush. Anyone know what this stuff is and how I can get rid of it for good? I scrubbed the entire steps completely clean 2 weeks ago and this stuff is back worse than ever. It’s incredibly slippery too.
Pool owner for 4 years, never dealt with this type of algae.
- Thread starter mtc89
- Start date
Looks like mustard algae to me. Hot weather and an improperly balanced pool will bring it on. There's a blog on TFP that discusses how to treat and prevent.
www.troublefreepool.com
Mustard Algae
Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.
www.troublefreepool.com
It looks like black algae as seen here: https://www.troublefreepool.com/blog/2019/01/18/black-algae/
Yellow algae is more of a "dust" of algae and is easy to brush as it just goes "poof". It can be a pain to get rid of though.
Yellow algae is more of a "dust" of algae and is easy to brush as it just goes "poof". It can be a pain to get rid of though.
- Jun 22, 2014
- 52,061
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
- Jul 17, 2019
- 4,078
- Pool Size
- 13000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Do you have a recent set of test results you can share, ideally from your own test kit and not test strips or a pool store? That will give us more insight to help.
Katodude
Silver Supporter
- Aug 22, 2017
- 3,004
- Pool Size
- 15000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
It looks like Black Algae to me. Bad news, there is a lot of it. Good news it looks localized. I personally dont like a wire brush.
I would hit it with a pressure washer (assuming your plaster is in good shape). Then I would get a few gallons of the strongest LC you can find and dump it straight over those steps and it will wash over the newly cleaned spots. I would do that chlorine dump once a day for a couple of days.
Then, and this is really important you will need to keep your FC at 20% of your CYA for a few weeks just to make sure it’s really dead. Also brush that stop regularly since its near the steps and probably does not get a lot of good circulation.
Now, join the BA club and you will have to keep your FC elevated for the rest of time. If you have a SWG never less than 10% if not then never less than 15%. When you FC drops it will come right back.
I would hit it with a pressure washer (assuming your plaster is in good shape). Then I would get a few gallons of the strongest LC you can find and dump it straight over those steps and it will wash over the newly cleaned spots. I would do that chlorine dump once a day for a couple of days.
Then, and this is really important you will need to keep your FC at 20% of your CYA for a few weeks just to make sure it’s really dead. Also brush that stop regularly since its near the steps and probably does not get a lot of good circulation.
Now, join the BA club and you will have to keep your FC elevated for the rest of time. If you have a SWG never less than 10% if not then never less than 15%. When you FC drops it will come right back.