On this page
Aquariums are calm, clean-looking and easy to forget about as a health risk. Most of the time they are harmless, but tank water holds bacteria, and a few of them can infect people.
Key figures
- 5 CDC higher-risk group: children under this age
- 65 CDC higher-risk group: adults this age and older
What the CDC lists
The CDC’s page on pet fish lists germs fish can spread, including Salmonella and Mycobacteriosis, better known as fish tank granuloma, a skin infection that usually starts on the hands of people who work in aquarium water.
The CDC also notes that children under 5, adults 65 and older, and people with weakened immune systems are more likely to become seriously ill.
The CDC’s habits
- Wash your hands with soap and running water after touching fish, feeding them, handling equipment or cleaning the tank.
- Wear gloves when cleaning or caring for the aquarium, especially if you have cuts or wounds.
- Clean equipment outside the kitchen, in a bathtub, laundry sink or outdoors, then clean and disinfect the sink.
- Do not let children under 5 clean or handle aquarium items.
Signs to mention to a doctor
A red bump or sore on a hand or finger that does not heal after working in a tank is worth showing a doctor. Mention the aquarium, since fish tank granuloma is uncommon and easy to miss.
Starting a siphon by sucking on the hose puts tank water straight into your mouth. Use a self-starting gravel vacuum or fill the hose with water first.
The new fish quarantine guide addresses the animals entering the system. The water-change guide covers another routine task that brings hands and equipment into contact with aquarium water.
Questions people ask
Can you get sick from fish tank water?
It is uncommon, but yes. The CDC lists germs including Salmonella and the bacteria behind fish tank granuloma.
What is fish tank granuloma?
A skin infection, usually on the hands, caused by Mycobacterium bacteria in aquarium water. It enters through cuts.
Should I wear gloves to clean my aquarium?
The CDC recommends gloves when caring for an aquarium, especially if you have cuts or wounds.
Is it safe for young children to help with the fish tank?
The CDC advises that children under 5 should not clean or handle aquarium items. Older children should wash hands afterward.
Where these figures come from
- Fish, Healthy Pets Healthy People Centers for Disease Control and Prevention · cdc.gov
Figures last checked September 2026.
