2 year update
The sharks were finally moved out of a tank and into their own lagoon yesterday. They have become increasingly aggressive and will bite one another at feeding time, holding on for 10+ minutes and drawing blood on several occasions. The female being the main problem. I have had in increase their feedings to help prevent this. They like to rest side by side, so it may remain a problem even though there is much more space.
They are both 25 inches at this point and weight ~ 5 pounds. So in two years, they have doubled in length. Their width is impressive. The claspers of the male have recently begun to increase in size too, I'm guessing another 6 months until maturity. The female probably has 18 + months to go. Based on growth thus far, I would estimate that they are around 3 years old.
Also about 1 month ago the male, while striking the food, snapped one end of the aquatongs off and ingested it. The entire rubber tip and about 1 inch of the hard plastic, gone. It took three weeks for it to pass, but it did. If something can go wrong, it will with these.