If you have a new account but are having problems posting or verifying your account, please email us on [email protected] for help. Thanks :)
Hello All, This is just a friendly reminder to read the Forum Charter where you wish to post before posting in it. :)
Hi all, The AutoSave Draft feature is now disabled across the site. The decision to disable the feature was made via a poll last year. The delay in putting it in place was due to a bug/update issue. This should serve as a reminder to manually save your drafts if you wish to keep them. Thanks, The Boards Team.
Hello all! This is just a quick reminder to ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere.

Green algae/slime removal from concrete?

  • 20-12-2022 4:08pm
    Registered Users Posts: 5,529 ✭✭✭ Duff

    Hey guys,

    Last spring we got some of our garden levelled off and concreted for the dogs. I've been keeping it clean by pressure washing it every few months. However, over the last two months or so the concrete has become completely covered in a green algae like substance which turns into pretty much slime when it's wet. It's a nightmare to get rid of. Any tips to get rid and stop it coming back as the dogs come into the house trailing it everywhere and leaving the place smelling like an aquarium! Cheers.


  • Registered Users Posts: 3,863 ✭✭✭ 10-10-20

    Hi, green slime would normally indicate that there is standing water or a high water-table in the area, leading to it remaining wet and hence the algae growth. Could this be correct?

    A photo of the affected area would help if you need better guidance. 👍️

  • Registered Users Posts: 8 Duarte1974

    Try applying a product like Moss Buster next time after you power wash the patio. Just be sure to keep the dogs off it until it has dried/ in line with the instructions for use.

  • Registered Users Posts: 8 Tom_Tripland

    You have to address the source first prior to cleaning or treating the moss/algae. Try salt, vinegar, and bleach.

  • Registered Users Posts: 1,074 ✭✭✭ ruwithme

    "Wet & forget " 1 litre of this product, add 5 litres of water & apply using a knapsack sprayer. Discovered this product some year's back now.

    Apply it today & come out tomorrow morning & you'll see it already working.give it a good soaking, ideally on a calm evening, when some rain in the forcast days ahead.wear eye protection & a good quailty filtered face mask.