Studies have shown that people who own a tropical fish are calmer and suffer from less ill health than those who don't. Dogs and cats are also known to have therapeutic benefits. Stroking a dog or cat has been proven to provide a calming effect on the brain. But the simple observation that watching fish makes people calmer and healthier is also backed up by studies. A freshwater or a tropical fish tank brings an increase in health and wellness and gazing at these kinds of aquariums is peaceful and relaxing.