Best method I have ever found to get rid of fleas is also the cheapest. Place a saucer or low rim pan (aluminum pie pan is awesome) half full of water on the floor, put some Dawn dish soap in it, place a direct light (desk lamp is perfect) over said pan, turn out all lights in house except this one.
Be prepared to be shocked at how many fleas are in the water (dish soap kills them), repeat for a few days until no more fleas are in water. Depending on size of house may have to either move or set-up a couple "traps"
THIS. This is how we annihilated a ridiculously infested house of the little critters. I would do this and put the DE dust down on the floor, though I wouldn't do this in the room with the tanks unless everything is super sealed and you sprinkle close to the floor so no dust gets in the air. Vacuum up 8-10 hours later. Those two things alone and you shouldn't have to bomb.