Bob-O gives great suggestions. Since your well water is probably high in iron and oxygen poor I would consider aeration as one of the first items to do. If well water will always be available to keep it full during the summer months and drought times I would lean towards bottom diffuser aeration. Thus lifting the entire water body the number of times per day that is needed. If have the possibility of having very low water and a heavy fish population you may want to surface aerate. Keeping your supply of oxygen above the demand is the key. Depending on the shape of your 1/4 acre pond a small 1.5/ 2.5 cfm compressor may be enough, just depends on the shape of the pond.Small compressors do not cost much to operate and there are a multitude of options available to get your pond aerated correctly. You also mention junk rock. Is this concrete or actual natural rock. Take your time do it correctly and enjoy the journey.
