Photos: (left) Zebra mussel on moss ball, courtesy BC Conservation Officer Service, (right) zebra mussels contained on moss balls first discovered at a Seattle pet store, courtesy US Geological Survey.

By Kevin Rothwell

Online purchases of concern

Aquarium owners asked to careful with algae moss balls

Apr 7, 2021 | 3:35 PM

A common item used to keep aquarium water sparkling is a continued concern for the Okanagan Basin Water Board (OBWB).

The board was updated on the latest scare involving the imported moss balls containing invasive zebra and quagga mussels. The infected moss balls were initially discovered in Washington State, which then prompted swift action by the B.C. Conservation Officers (CO) Service to check with aquarium supply stores across the province. The moss balls were imported from Ukraine and Singapore.

“Eleven hundred shops were contacted and 3,000 moss balls surrendered or seized, some were dry, some were in tanks and hydrated, water was also tested from peoples’ aquariums, and none in B.C. were found to be viable is the information I have received, that said there were some viable moss balls reported in Eastern Canada,” OBWB communications director Corinne Jackson told the board.

The CO Service has reported excellent cooperation from the aquarium industry.

There were several infected moss balls discovered in the lower mainland, Terrace and an online purchase in Invermere.

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“People were purchasing these thing online, with invasive mussels, which created another level of anxiety,” Jackson added. “The E-trade is a concern now, although there has been excellent support and engagement through Kijiji and Amazon, there is some concern there is this additional route for these moss balls to enter.”

Marimo Canada, one of the top online suppliers of the product, stated on its website that it has halted online sales, “because of a government international investigation regarding invasive zebra mussels that were spread with some Marimo. We always had a very clean product but every sale is shut down during the investigation and we will respect that.”

Some countries like New Zealand have placed an outright ban on the importation of Marimo moss balls under 2006 bio-security legislation.

If you have the moss balls in an existing tank do not flush them down the toilet, they must be frozen or boiled before being disposed of.