I recently installed the SP7UV into the tank. I followed the instructions from the manual. And after 24 hours, I released the fish back into the tank after cleaning. The fish are all under the device and some aren't moving anymore. One is stuck right next to the device, and the a few are flipped over. One is upside down and cannot get back to equilibrium, a few are just dead, I guess. I am not sure what is going on. I am an amateur and my dad bought my device. I really love my fish and I am so sad that this is happening. Any insight?