How to Care for a Marble Gar in an Aquarium

Gar fish are considered difficult pets to keep by aquarists, and often recommended for experienced aquarium enthusiasts. The marble gar, also called the spotted gar or spotted pike Characins, is of the genus, Boulengerella. These lengthy fish are rare, but can be found in some aquarium fish stores, locally and online.

Called living fossils by the scientific community, evidence of gar fish dates back more than 100 million years. These predator fish are tubular in shape. With their long toothy snout, marble gar are primarily piscivores, or fish eating. High on the aquarium fish food chain, the marble gar is nonaggressive and no danger to comparable sized tank mates. Your marble gar's skin is covered by a protective coat of hard, diamond-shaped scales making him impenetrable to predator fish. Able to breathe atmospheric air, gar fish have a swim bladder, which allows them to live in minimal-oxygen watery environs.

To keep marble gar you'll need an oversized aquarium. Aquarists recommend keeping marble gar in an aquarium of 200 to 400 gallons, or greater. Your marble gar will adapt to his tank size and usually grows to no more than 2 feet in an aquarium. Lighting for your marble gar's aquarium should have a low to medium low rating. Marble gar are ambush predators and need places to hide while stalking prey. Floating aquatic plants serve well as hiding places and a built-up hardscape of rocks and plants also will suffice. While marble gar see smaller fish as bite sized, they are compatible with most aquarium fish closer to their own size.

Finding fare for your piscivorous marble gar is a challenging issue. Primarily fish-eating, marble gar need vitamin supplementation to go with their carnivorous diet. In the wild, gar fish dine on many minnows and guppies, but also large insects, shrimps, beetles, crabs, crayfish and small birds or mammals venturing too close to the water's edge. The inexpensive feeder fish sold at aquarium stores are often kept in less than ideal conditions, and a possible source of bacterial and parasitical infections. Frozen foods, with balanced vitamin and mineral nutritional supplements, are available and preferred by experienced marble gar aquarists. For feeder fish, marble gar enthusiasts use mollies and guppies, and prefer to breed their own.

Aquarium water is the most important consideration for marble gar. Your gar's tank should be kept clean and well-circulated using power heads, a fluidized bed filter and protein skimmer. Frequent water changes are needed to ensure nitrate levels stay low. Marble gars can tolerate varying pH levels, but the ideal range is 6.0 - 7.5. The temperature range for marble gar is 60 to 90 degrees Fahrenheit. Since gar often breathe air, they require a few inches of breathing space above their aquarium. Never house plecos with marble gar as they may wound your fish, causing infection, trauma and scars. Marble gar are jumpers and a tight-fitting lid is essential for these pet fish.