We fibreglassed any holes left from gutting it. The pond is not filtered, not enough bioload to warrent it. I am though looking at a solar water fountain for it just to get some surface movement.
Please be aware - - - It is highly illegal to knowingly degass a fridge or freezer into the atmosphere, it needs to be done by a professional that can collect it correctly. The freezer pictured had stopped cooling, after getting it checked we were able to gut it ourselves without deliberatly releasing the gas as there was none left to release (freezer had leaked the refridgerant thats why it seemed to run perfectly but no longer cooled)