fozz, I would not be in any hurry to aerate.With the melting snow you will have clear to semi clear ice when it refreezes.With your surface water drainage you have some water movement. It is still winter and a little early to force the warmer lower waters to the surface. I would imagine that you have plenty of DO.A little sunlight goes a long long way this time of year.I would not turn your system on before April. Just my .02 cents. Ted