Tank currently used for compost tea, to add bacteria rich nutrients to the system, and so I had quite the algae bloom. Got a handful of duckweed for free from the local home center and the algae has gone down. Now I just have to deal with the snails (free protein for the right fish) that came with the duckweed.
The other tank in the background contains the Koi and Comets.
After the system has aged I want to add other cold tolerant fish such as grass carp. Any other suggestions?