Once you have over a thousand dollars or so invested in your aquatic life a portable generator makes more and more sense- especially if you live in areas where power outages are common.
I just survived three days without power and did not experience any losses at all. I have battery pumps for each tank I have running until we can get the generator fired up.
It's hard to swallow the expense of a generator, but once you do you will seriously never regret it.