Please be aware that there can be bacteria in your aquarium causing very serious infections in humans. Mycobactium marinum is carried in the fish and water. It can enter your body via small skin cuts or scrapes you might not be aware of. The resulting infection is severe and antibiotic resistant. Successful treatment can take up to a year to complete and usually involves surgery on the affected area. I caught this infection on my left hand a year ago and just now have a diagnosis. The infection has made a mess of the top of my hand and has spread to the lymph nodes going up my arm to just below my armpit. Even though it is a rare condition, use caution when you put your hand in the tank water, especially if you have any open cuts or sores.This is no joke.