A new study has found that some aquariums contain bacteria that are capable of producing serious infections in humans.

The presence of Salmonella and other enteric pathogens such as Aeromonas in aquarium water has been known about for some time. According to the results of a study by a team of microbiologists from a number of Australian academic institutions, research has shown for the first time that fish tanks can act as reservoirs for potentially dangerous multidrug-resistant strains of Salmonella capable of causing serious illness in humans, particularly young children.

Scientists recommend that information be produced and distributed to pet shops and their customers to inform them of safety precautions in order to reduce contamination risks from bacterial pathogens that might be living in their aquarium water.

Among the recommendations, says the New York Times, are guidelines to change a third of the water every fortnight, and to follow manufacturer’s guidelines on cleaning filters. It advises against washing aquarium accessories in the kitchen or bathroom sink: “If you have no other option, then thoroughly clean and disinfect all the surfaces used with a bleach solution of four tablespoons per liter of lukewarm water. Rinse these surfaces well before reusing.”