It took three applications of Demize EC and Precor IGR to finally control the sand flea infestation which is epidemic due to a severe drought here in East Texas. The first application was done with four ounces of Demize and two ounces of Precor in two gallons of water which was sprayed onto the floor in two successive application on immediately after the other. The second and third applications were done with two ounces of Demize and one ounce of Precor in one gallon of water. The second application was done a week after the initial treatment and third application was done a week after the second application. It thus took two weeks (fifteen days) to do the three treatments, and about eighteen days after the first application the fleas had disappeared. Haven't had any more fleas since.
The only thing I found slightly objectionable about Demize EC is the odor. But it is a trade off between an "orange" scent and the normal insecticide chemical odor. Fortunately it didn't linger for very long. It is a small price to pay for the effectiveness demonstrated by a mixture of Demize EC and Precor IGR.