Is it better than to have the check valve in the water vs at the compressor? I am planning on buying two vertex diffusers this month which I believe have the check valves in them. Any reason to run one at the pump?
Will a standard, adjustable air compressor pressure relief valve work?

I went from having a clear weed free pond to in the last two summers (record heat and sunny) having weed filled can't to the point it's unfishable.

I believe much of that is my fault as I only ran the aerator on the hottest days and not at all in the winter do to the compressor being noisy.

That said, the water clarity is still very good even with the new compressor running two cheap diffusers at this point. There is good visibility down to around 8ft and then you see decaying weeds.

I am hoping by running the aerator and raking the bottom I can prevent those weeds from turning into muck and prevent some regrowth. There is not much muck currently on the bottom less than 3 inches at this point.

As long as over aerating won't hurt anything thing I would rather have too much than not enough. It only cost me about $12 per month to run the compressor so that is not a concern.

A lot to learn here. Thanks for all the help.