Hondo - YES you will need a check valve on the end of the hose - good thinking. I took it for granted and assumed; both bad ideas. Don't get a check valve with a real stiff spring, better w/ low tension spring or no spring. Water draining back up the air pipe to the water line & then freezing is ONE VERY GOOD REASON NOT TO: RUN OR AT LEAST SHUT OFF YOUR COMPRESSOR DURING WINTER. A frozen ice plug in the air pipe causes big time problems that usu damage pumps. They are not designed to with hold their air. That is why I recommend a pressure relief valve that will allow the air to escape and not harm the pump if any type air block happens.
If you don't shut your pump off during winter no problem; providing no power outage.

Your outside plug should have two small buttons on it 'test' and 'reset' if it is GFI.

How you going to hold your airline on the bottom? Many use 10 ft sections of rebar/rerod abt 1/4" -3/8" dia or stranded cable. It has to weigh abt 5 lbs/ 10 ft of length..

Easy way to install your 'bubbler'. Strech the airline out full length along the pond. Tie a heavy non-rot cord (sm rope) to the weight/end. Walk around to the other side w/ the end of the rope and drag it in. You may have to add a temporary extension on the rope to get around the pond. Leave rope atached all winter; use it to pull it out in spring or as needed. Simple, very easy & no monkeying around in a boat pulling weighted airline. No float needed; know where bubbler is by leaving it 'on' during installation.

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aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
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