Originally Posted by t2000kw
You can hook up some tubing and route the exhaust from inside to outside, but you also have to supply air for the generator to run. Most homes probably leak enough air to do this. If you smell any exhaust, your re-routing of the exhaust is not good enough.
As for the filter media and the bacteria, I've read that you can remove it form your filter and put it in your tank right away, then when the power is back on, put it all back together after you've cleaned your filter out. Supposedly it is safe in the tank but not in a stagnant anerobic chamber such as a canister filter.
Submerged in the tank keeps it wet but not aerated, decomposing debris and dying bacteria use up more oxygen that fish need as well. Better to remove the media to a sealed plastic bag, it stays wet and aerated. When bad weather is possible, be sure the filter is rather clean.
Submerging in the tank really only makes sense for something like a biowheel, that if not wet will dryout, even then, a sealed plastic bag is smarter.