4'x6'x1.5' pond help

Unfortunately my mom doesn't listen to me. She said sugar gliders hibernate too-and killed mine by throwing him outside on a 50 degree day.
no fish really hibernate, and what i do know is you're not supposed to feed them in winter.
 
ty pupies and flar. i know that it is to small for koi.isnt the min for koi like 500 gallons per fish?
 
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