Q In attempting to eliminate box elder bugs from the south side of our home, my husband mixed Cascade dishwasher detergent in water and sprayed the house and windows. He left this solution on for many hours and then hosed it off. We now have windows with streaks that I cannot remove. I have tried vinegar, window cleaners, Jet Dry and various spray cleaners. Is there a solution that I have missed?

A Take that cleaning bucket away from your husband. You never, ever put a cleaner on glass and let it dry, especially one with as much muscle as dishwasher detergent. It can ruin glass.

Dishwasher detergents typically contain high levels of phosphates. They're different from dishwashing detergents, such as Dawn.

Dishwasher detergents are designed to be short-action cleaners -- in contact for a short time and then thoroughly rinsed off. They can attack or "pick out" minerals such as lead from glass, altering the surface. Under a microscope, the etched surface appears as rough and cratered as the moon. Unfortunately, that's permanent unless you pay to have the glass professionally buffed to remove the scratches.

But there is hope. It is possible that your windows are not etched, that instead you are seeing a film of the cleaner that's been baked onto the surface. To test this possibility, toss clear water on the glass. If the streaks disappear, only to appear again when dry, the glass is etched.

If the streaks remain visible and there's no change in appearance, wet or dry, then it's probably a film. The challenge, then, is to remove the film.

Call in a professional window cleaner who uses Crystal Clear cleaner, such as Squeegee Squad (763-780-0492) or Final Touch Services (651-641-1018). The product, unavailable to homeowners, might remove the film from your windows.

Now back to the bugs

Hand the bucket back to your husband with the following solution: 1/2 cup laundry detergent in 1 gallon of water. With a hand sprayer or hose end attachment, spray the bugs with the solution. Keep the solution away from windows. Remember, this treatment affects everything it comes in contact with. You may need to apply more than one treatment, but it will help to keep box elder bugs out of your house.

Includes information from Winsol Laboratories in Seattle.

Send your questions to Fixit in care of the Star Tribune, 425 Portland Av. S., Minneapolis, MN 55488, or call 612-673-7032, or e-mail fixit@startribune.com. Past columns are available at www.startribune.com/fixit.

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