I used to have a tank of baby guppies on the bottom shelf of a stand. The tank was open top, I was too lazy to buy a glass top. Well we have a HUGE Berenese moutain dog named Max. He is a big slobbering type dog that has quite the love of drinking water, it doesn't matter if it's from the toilet or his dish. I thought my number of baby guppies was getting smaller, but never paid much attention to it, till the day I caught Maxy drinking out of the fish tank. Apparently he was slurping up more than some tasty fish tank water, he was getting some tasty feeder guppies too!