Glofish or Zebra Danios?

an article submitted by Exotic Aquariums
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Glofish do not exist in nature. They were created in a laboratory. Glofish are genetically modified zebra danios or Brachydanio reri. Geneticists in Singapore added the fluorescent gene from sea coral to zebra danio eggs. The result was the glofish. Aside from their genetically altered neon color palette they are identical to zebra danios.

These fish are vibrant under any circumstances. But they fluoresce or light up when they encounter environmental toxins. They were first created to do precisely that, detect environmental toxins. They were made available for sale to the general public in 2003.

Environmentalists have expressed concern about what might happen if these genetically altered fish made their way into natural rivers and streams. The creators of glofish state emphatically that these genetically engineered fish are not an ecological threat. Glofish, like regular zebra danios, can only survive in tropical waters. Aquarium water temperature should be between 64-74 °F. In the six years since their release for sale to the general public, they have not seemed to pose any ecological threat. While the sale of a genetically altered fish simply because they look prettier than their “natural” counterparts may be ethically questionable, they are beautiful fish.

So far Glofish have proven to be every bit as hardy as regular zebra danios. There is, after all, only a single gene that differentiates the two.

Glofish come in a variety of brilliant rainbow colors. They can be purchased for around $6 or $7.

Zebra Danio

Zebra danios are a member of the Cyprinidae family. They are native to eastern India. They are hardy and active fish with peaceful temperaments. They make good additions to community tanks provided they are housed with fish of similar temperament.

Zebra danios have a five year life span and will grow to length of about two inches. They thrive in slightly acidic to neutral water (pH 6.5-7.0) and prefer a rather chilly water temperature of 64-74 degrees Fahrenheit. They can, however, adapt to the warmer climate needed for most other tropical fish. They are surface dwelling fish that favor moving water. Zebra danios are shoaling fish. It is not advisable to purchase a single fish for your aquarium. Nature intended them to live in a community.

Zebras are omnivores that can survive just fine on a diet of tropical fish flakes. Both sexes have to pairs of barbels on either side of their mouth.

In their genetically unaltered state it is easy to tell the males form the females. Males have blue and gold stripes. Females have blue and silver stripes. The female tends to be larger and fuller bodied than the male. This would be the distinguishing factor in the genetically altered varieties.

Breeding Frankenfish

Zebra danios are some of the easiest fish to breed in captivity. Spawning can be triggered by raising the water temperature up a few degrees near dawn. This will trick the fish into believing it is mating season. When spawning occurs 3-500 eggs will be scattered across the breeding tank floor. Remove the adults to prevent them from eating the eggs.

The fry will hatch in 2 days. They can be fed liquid fry food or small amounts of powdered eggs. In a week or two they will be large enough to eat brine shrimp or finely crushed tropical fish flakes.

Glofish or Zebra Danios?

has been viewed times since June 30, 2009.