Do you have shower doors you want to hide due to grunge and grime. If you feel yours are not "see"worthy, here are a few cleaning tricks. First scrub down the glass with lemon-oil polish and a scouring pad (it might take some effort to cut through the goo). Another good rub-a-dub scrub is sodium carbonate sold in pure form by swimming-pool dealers under the name "pH increaser." For particularly stubborn mineral stains that might have built up over a long period, tackle one small section at a time by suspending a vinegar-soaked rag from small suction cups (with clips or hooks) so it hangs up against the film-covered glass. Once it softens the mineral deposits, remove, scrub and reposition to another area. Finally, when you're through, keep things clean by using a squeegee to remove excess water from both doors and walls after each shower. And that's the On The House tip for today.