Female cat fleas remain on the host (unlike most other fleas) and lay about 20 to 30 eggs per day on the animal. Cat flea eggs are pearly white, oval, and about 1/32 inch long. The eggs are smooth; they readily fall from the pet and land on surfaces like bedding and carpeting in the animal’s environment. They hatch in about 2 days. The whitish, wormlike larvae feed on dried blood and excrement produced by adult fleas feeding on the pet. Larval development is normally restricted to protected places where there is at least 75% relative humidity. They feed and crawl around for 5 to 15 days at 70° to 90°F before they build small silken cocoons in which they develop into adult fleas (pupate). The pupae are usually covered with local debris for visual camouflage. Flea larvae develop more quickly at higher temperatures. At cool temperatures, fully formed fleas may remain in their cocoons for up to 12 months. Warm temperatures and mechanical pressure, caused by walking on the carpet, vacuuming, and so on, stimulate emergence from the cocoon. At room temperatures, the entire life cycle may be completed in about 18 days. An adult cat flea generally lives about 30 to 40 days on the host; it is the only stage that feeds on blood. Fleas may be found on pets throughout the year, but numbers tend to increase dramatically during spring and early summer.
For this reason I used the bug bombs several times every few weeks to make sure I was killing any new fleas that hatched. To truly stop an outbreak you need to use a variety of methods. Treatment on the pet, vacuuming places where the pet goes, and possibly even treating outdoor areas where fleas are likely to live.
Anyways, fleas aren't the probplem that the OP is concerned with so it doesn't matter. FWIW, I used to see lots of spiders and silverfish in my house. The spiders were probably living on the silverfish. After using the bombs I haven't seen either in a long time. I'd just cover up your tank really well. I like the plastic tarp idea. Your tank should be okay without power and when you come back in 3-4hrs just open all the windows to air out the house.