Recently I had to move my piranhas to a 165 gallon tank because their previous 55 gallon tank had a broken center beam and was beginning to cave outward. As we moved them, they began to slowly start to play dead. When we put them in the new tank, they sank straight to the bottom. The fish were still breathing and would move if we tried to pick them up to put them in the tank. This may be because the water of the new tank is too cold, but I am not sure because it has at least more than room temperature water. Some people say piranhas don't play dead and others do so I wanna know if their behavior is normal. Additionally, I won't be able to return to the tank until a few days from now so I am a little nervous for them. Is this behavior similar to what other piranha owners experience?