I found several babies that I wasn't able to catch last fall and move into the bigger side alive!!

Normally anything that stays in the lower pond in the winter dies because I only have a de-icer on the bigger side with the Koi. Anyway, I went out there last week and there were about 5 of the babies from last year and they had all survived. They all look great and are very active. In January the pond totally thawed so that must have left any gases out and allowed the fish to live.