Are there any guidelines on how much aeration per fish to use?

I've been using a fountain in my pond on a timer, set for off and on throughout the day and particularly late night/ early morning when oxygen levels (I have plants) are lowest. That turned problematic when a very windy night blew out a couple hundred gallons!

I have a low occupancy unfiltered pond (with a lot of surface area) of about 600 gallons with 6 fish (medium to small size). Water temps are now in the 50's and 60's. I'm thinking of a Tetra 60 or 100 with a micro bubbler.  Or do I not  need to worry? There is not much debris in the pond, so I think little anaerobic activity beyond fish waste.

Fishy Jeff

Nossie (or someone) - is it true that too much aeration is a bad thing? I read something somewhere...bubbles under the skin? or something of the sort....I like long airstones against the back wall plus super strong filters so my tank is full of teensy bubbles. Too much?
Jeff- sorry to hijack. Do you have pics of your pond? Thats my ultimate dream...