Hello, I once again have more questions. I was wondering why black piranhas get bumps on their chins and why these bumps sometimes turn white. I was also wondering if you guys think I'd be happier with a black piranha in the long run. I have never owned any pygos or serras, so I do not know which are better fish in general. Now, I am also wondering how big a black piranha would grow in a standard 125 gallon tank after about 3 years. Next, I was wanting to know the average lifespan of a fully tank raised black piranha. Now, I know you would probably tell me to do my research on their lifespan, but I already have. I have gotten several answers, such as 4 years, 10 years, 6 years, or 10-30 years. I just want to know what you guys think would be a more likely lifespan of a tank raised black piranha if you really pampered it.