RLewis,
You have a choice between running an air line the 75 yards to the pond from a compressor or running electricity the 75 yards to the compressor at the pond. Pros and cons for either way...but my personal choice is to run the air line (pvc pipe or poly tubing). Water and electricity don't mix gracefully.
Once you get air to the pond, you will need to install the diffuser with the weighted tubing attached at the length required to reach the deepest part of the pond. This can be easily accomplished in a pond either with a small boat or a rope strung across the pond on the opposite side and pulling the diffuser and air line to the desired location.
