Hey guys. I was without power for over 6 days with my 90 gal reef tank. By day 3 after only using battery operated bubble box i started to scramble because tank was way too cold it was in the low 60's and fish were lathargic. I had a friend lend me a small generator which i now think is a must have for all aquarium owners. I used a 800 watt gnerator from harbor freight which cost roughly $100-$125. Its a 2 stroke oil amd gas mix. Less than a gallon of gas ran this thing for 6-8 hrs straight. I had my sunpod 2x250 watt lights running. Which lit up my downstairs which was a bonus. When lights werent being powered i had my 250watt heater running. my house was 58degres during this time. I also ran my pump to circulate the water and a koralier to give the water flow. This little powerhouse is about the size of a 12 pack of bottled bear amd kicks ***. Small and light enough to store its a must have. I alreasy ordered mine off there website but u can find them in ur local harbor freight store.