My friend's Piranha keep having babies and he gave me 5 or 6 on two occasions each time they died within a week. they are in infant stage and are no bigger than a cm. Why do they keep dying, what am i doin wrong . The water is clean the temp. is at 75 to 80 degrees:and they also won"t eat although i don"t try n feed them till 5 days after being in th e tank. Someone help please cause he has more babies!!!