The compressors that are used in aeration systems for ponds are oilless...... I won't recommend using an oiled compressor.

Check into the diffuser CFM operating range if you are doing a DIY system. Also, don't run a lot of air pressure to the diffuser. Typcially all that is required is 3/4 psi or slightly less per foot of water depth at the diffuser location.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).