Went through much the same this time last year, power company wanted to move the underground power from one side of the street to the other. Two ~6 hour outages and one ~10 hour outage in a week. I taped a blanket over my tank but left some gaps around the hood to allow for some gas exchange. Also raised temp a couple degrees C, vacuumed gravel (less decomposition consuming oxygen), topped the tank up to 1cm below the glass covers and aerated like mad beforehand.
