I have two 24-25" silver arowanas. I do beleive that I have a male and female. The physical traits that differ between the two. Jaw structure(Credit to JohnPTC), the one which is believed to be the male has a boarder jaw that extends above the head and is at less of an angle compared to the female. Observing pics of only known confirmed female on MFK(Delgado's) will support this. Body shape the female seems to have a taller broader body then the male, also the trailers on the lower fins are much shorter then the male.
These are only observations and I have no positive proof of sexing. These two have been living together since May in a 180g tank. Temp 80 degrees F, pH at 7.4 weekly 50% water changes. On a diet of frozen market shrimp, jumbo cichlid sticks, freeze dried krill, crickets and earthworms. The male has grown 4" and the female has grown 6" since May 17th 2007.
In the pics below the male is the top pictured.
These are only observations and I have no positive proof of sexing. These two have been living together since May in a 180g tank. Temp 80 degrees F, pH at 7.4 weekly 50% water changes. On a diet of frozen market shrimp, jumbo cichlid sticks, freeze dried krill, crickets and earthworms. The male has grown 4" and the female has grown 6" since May 17th 2007.
In the pics below the male is the top pictured.
