I really haven't done anything else. The water temp is in the 50's and the fish are doing fine. I'll wait until spring before I do anything else to it.
Jusy a quick update, The water has warmed to the 70's. It's clear but the pool looks green because of aglae growing on the plaster. I put some larger plecos in but so far they haven't done much to clean the algae off. The plants in the bog filters are just beginning to grow so hopefully they will cut down the algae growth once they really get going. The biggest problem I've run into is the sand filter is a pita. It clogs too quickly and it takes alot of water to backflush it so often. So I think I will replace the sand with Hiatt Tribase pelletized carbon and see if that works better. If not there's a product called PermaBeads that replaces the sand. From what I've seen people like it aot but it is really expensive. Other than that everything is going pretty well. The Koi have grown alot and the channel cat has gotten pretty big.