1.) Bramble placed in the pond will provide shelter for the younger fish.
2.) Are you sure you want CC breeding? Ladder stocking them is a common method of controlling populations. Breeding beds will promote a self sustaining pond, but could get out of hand. This is difficult to access, I know...just food for thought.
3.) Shop compressors are not efficient in pond aeration. It is hard on the compressor, cost more to operate, and may lead to oil sheens in the pond. Oil will get carried in the air stream if it is not an oil free compressor.
Bringing up the aeration slowly, but not too slow, is a smart thing. The rule of thumb here at PB is to turn the whole pond over at least once a day. Shooting for the ability's to turn it over a few times a day is a good place to start the system design. This way you can run only at night (or day) should you chose and still get the turn over in a day. Starting and stopping the system for 15 minute runs will reduce it's effectiveness. Every time it stops. the momentum of the water movement slows to a near stop too and the system has to get it all moving again. Plan to bring it up slowly to a point where it runs for several hours at at time / once a day.
Common practice is to start it up the first day for 15 minutes and smell for "the stink". If it starts to stink, STOP. Try again the next day with hopes of getting a longer run and so on. If NO stink, just double the run time daily until you get to the run length you want/need. We can get into system design if you are so inclined to step away from the open hose run by the compressor. That is not a good way to go.
