Check Your Aquarium For Zebra Mussels

Invasive Zebra Mussels Found in Aquarium “Moss Ball” Product in Pet and Aquarium Supply Stores

AUSTIN – The Texas Parks and Wildlife Department (TPWD) and other wildlife agencies are urging stores that sell aquarium products to remove a “moss ball” aquarium plant product from their shelves. They ask customers to dispose of the contaminated product after discovering the invasive zebra mussels are hitchhiking on these products in states around the country, including Texas.

These “moss balls” are a species of algae that form green balls up to a few inches in diameter, and stores sell them as an aquarium plant under names such as “Beta Buddy Marimo Balls,” “Mini Marimo Moss Balls,” and “Marimo Moss Ball Plant.” They may be sold separately or provided with the sale of Betta fish. We believe these moss balls have been imported from Ukraine and distributed across the continental U.S.

You can recognize Zebra mussels as small shellfish with triangular, brownish shells, often with their namesake zebra stripes, that may be attached to or growing inside the moss balls. They are tiny, growing to no more than an inch in size, and the individuals found on the moss balls in Texas were less than a quarter of an inch long.

“Petco stores have been working diligently to remove these products from their shelves, and I have informed PetSmart of the presence of zebra mussels within this product,” said Jarret Barker, TPWD Assistant Law Enforcement Commander. “We urge any other pet and aquarium or a retail store selling these ‘moss balls’ to remove this product from shelves and discontinue future sale.”

Aquarium owners are urged not to buy this product and safely dispose of any that they have purchased. To dispose of the product, you can completely dry, freeze, or placing the moss balls into a plastic zipper bag and then put it in a garbage bag. It would be best if you replaced your Aquarium water and filters/cartridges or disinfect them. To disinfect Aquarium water before disposal, add one cup of bleach per gallon and allowing it to sit for ten minutes before disposing of the water down the drain. This method can also disinfect gravel, filter, and other structures, and we highly recommended if you find zebra mussels attached to the moss or in the aquarium.

Zebra mussels are highly invasive, causing economic and ecological damage when released into the wild. These aquarium products pose a risk of this species being introduced into new Texas water bodies and causing severe harm.

“Zebra mussels have already been introduced into many Texas lakes and are causing changes to the ecosystem along with damage to boats, water supply, and control infrastructure,” said Brian Van Zee, TPWD Inland Fisheries Regional Director. “It is important that we take all possible precautions to prevent them from being introduced elsewhere.”

Aquarium dumping is a well-known pathway for introducing aquatic invasive species as well-meaning pet owners release unwanted pets, unintentionally causing harm to native fish and wildlife. It includes the fish and aquarium plants and organisms like the zebra mussels that may be hitchhiking on these plants. We urge aquarium owners never to dump their tanks and learn more about aquarium dumping alternatives by visiting the TexasInvasives website.

“Invasive species such as these zebra mussels and snails can hitchhike in aquatic plants sold for aquarium use,” said Monica McGarrity, Senior Scientist for Aquatic Invasive Species. “It is important for staff at stores as well as customers to always check aquarium plants for hitchhiking organisms and to alert store management and not sell or buy plants with mussels, snails, or other organisms attached.”

To learn more about zebra mussels and other invasive species in Texas, visit the TPWD Stop Invasives website.