Author: Adam Denish, DVM

WRITTEN BYAdam Denish, DVM Veterinarian,By Adam Denish, DVM Perhaps you’ve wandered into the aquarium department of your local pet store and taken a good look at the faces of the fin-tailed. It’s easy to fall for the beautiful colors, the graceful movements and the soothing sounds of the water. If you feel like you’ve been hooked, read on to learn what decisions beginning fish hobbyists need to make when contemplating the details of adding a new aquarium to their home. Freshwater or Saltwater? Water covers about 75 percent of the Earth. In the assorted bodies of water, lifeforms have evolved to survive with varying amounts of dissolved salts and minerals, varying temperatures, oxygen levels and depths. When building an aquarium, you aim to recreate the conditions of the environment where the inhabitants have originated. The pet trade has broadly divided the aquarium habitats into freshwater (tropical) or saltwater (marine). A comparison of the components of these habitats will help new fish keepers make an informed decision about how to select an aquarium suitable for their lifestyle.

By Adam Denish, DVM I had finally done it. Each year at the school carnival, we could try to win a goldfish by throwing a ping pong ball into a small glass bowl. At the age of eight, I was allowed to have a chance. After two throws that went bouncing around the table, my last attempt was a winner. “Congratulations,” the game attendants said, then quickly netted a small goldfish and packaged him up in a plastic bag of water. Herbie spent the night in a plastic container. Over the weekend, my father picked up a glass fish bowl, a small bridge and some blue gravel. We cleared a spot on a side table and Herbie lived in that bowl for about two years. We would laugh at Herbie’s silly antics as he kept manically swimming circles around the bowl. Sometimes I dropped too many food flakes into the bowl or even forget to feed him. When the bowl became so cloudy that we couldn’t see Herbie very well, it was time to change his water.  While Herbie in his fish bowl is a nostalgic sweet memory, present day fish-owning has expanded, producing a variety of options for housing just one fish or an entire underwater community. While the simplicity of keeping a fish in a bowl may appeal to those hesitant to commit to pet ownership, educating yourself on the best housing appropriate for the fish you select is a necessary first step before bringing home a finned friend.   Can Fish Live in Bowls? While it is possible for a fish to survive in a bowl of water, consideration should be given to the quality of that fish’s life. Educate yourself first before any purchase to make sure you understand your responsibilities as a pet parent.  As an exotics veterinarian, I try to convince consumers to give all animals, including fish, the best life possible. Like other animals, fish breathe oxygen and release carbon dioxide, using their gills to extract oxygen from the water. In nature, the action of currents and photosynthesis by aquatic plants replenishes oxygen levels in water continually. Waste products are cycled naturally by bacteria, as well as a host of other creatures that serve as decomposers. While replicating the conditions of a river or stream would be difficult to do in captivity, using an electric-powered filter helps to address the basic needs of providing oxygen in the water and removing waste products. Filters operate with a replaceable activated carbon bag or cartridge that cleans the water chemically and biologically by removing organic waste and harboring beneficial bacteria. Using a filter in your fish’s habitat will improve its living conditions immensely.

By Adam Denish, DVM             You may be searching for the answer to the ultimate question, “How long will my fish live?”  Scientists around the globe have dedicated their careers to studying lifespans of people and animals to determine why some animals, like Galapagos tortoises, can live well over 100 years while a field mouse only lives two or three years. An animal’s life span is affected by a number of genetic factors including physical size, heart efficiency, metabolism, age of reproductive maturity and length of reproductive viability. Environmental factors including disease, predation, drought and starvation are also at play in determining the lifespan of an animal. When we pose the question of how long our fish will live, we need to consider how well the fish is fit for life genetically and then assess the environmental risks. While determining the life expectancy for individual fish can be more of a guessing game, we can use some indicators about size, reproduction and the environment to give some broad determinations. Size Indicators that Determine How Long Fish Live Physicist Dr. Geoffrey West has made a correlation between size and cell efficiency and applies methods he uses to determine the energy needs of different-sized cities to the way living organisms use energy. West puts cells of organisms on an even playing field and then scales their needs by a factor related to their physical size. West explains that if a mouse and an elephant both have the same number of heart beats in their respective lifetimes, the difference in life expectancy would be determined by the rate of their metabolism. The elephant lives a more efficient and longer life due to slower metabolism. We can take this assertion and apply it to tropical fish as well. It is true that larger fish like plecos, Oscars and clown loach have a longer life expectancy than small fish like bettas or killifish. These large fish are the elephants in the aquarium.