These are tattooed mollies. And they got the name because they were tattooed with random designs and numbers. These were imported and sold in major aquariums. People usually buy them in fours for the numbers these mollies bare on their skin, it's for 4D. What happens to these mollies after they are purchased for their numbers and after the numbers are bought, no one knows.
The bigger concern is about how these mollies are tattooed. The fish is being soaked in a solution that removes its protective slime that is necessary for protecting the fish against diseases. The fish is then punctured with a needle to inject the dye. As fish are very susceptible to diseases and infections, slight contamination of the needle or dye can cause a batch of mollies to die. Furthermore, the stress that the fish has to go through while being tattooed lowers its immune system making it even more vulnerable to infections.
Tattooing a fish or artificially modifying any part of it is actually being cruel to animals. Therefore, boycott tattooed mollies. Animals are to be cared for, not put through unnecessary pain for our pleasure.
