Wednesday, April 14, 2021

Mussels detected on moss balls in Montana pet stores

by Daily Inter Lake
| March 4, 2021 1:58 PM

Officials with Montana Fish, Wildlife and Parks recently detected zebra mussels in aquarium moss balls in pet stores throughout the state.

The agency went searching for evidence of the aquatic invasive species shortly after they were detected on moss balls in nearby Washington state. Moss balls, which are roughly 2 to 5 inches in diameter, are purchased for home aquariums to help absorb harmful nutrients in the water and limit the growth of undesirable algae.

FWP officials believe the items were imported from Ukraine to a distributor in California, where they were then shipped out to pet stores nationwide. According to a news release, the facility that imports the moss balls has been quarantined and all shipments of the items have been stopped.

All of the mussels detected in Montana have so far been dead shells.

However, live mussels were found on the aquarium products in both Oregon and Idaho and FWP is working closely with other states and federal agencies to address the issue, the news release states.

The agency has asked that anyone who recently purchased moss balls remove them from the water, place them in a plastic bag and then put them in the freezer overnight. Individuals should then dispose of their aquarium tank water down their household drain, not into any outside water resource.

“This is another reminder to never dump aquarium tank pets, plants, or water into Montana’s waterways,” the news release notes.

It is illegal to release fish and other aquarium pets into natural waterways, as they can impact native aquatic plant and animal species. If someone no longer wants their aquarium pet, FWP asks those individuals to find someone else who can adopt it, to turn the animal into a pet store or humane society, or euthanize it.

For more information on aquatic invasive species call 406-444-2440, and for more information on how to properly dispose of aquarium contents, go to