Ceramic Tile/ Cementitious Grout:
Clean only with PH Neutral cleaners available at Tile Stores and big box stores. Many of these cleaners say 'Neutral Tile cleaner' right on the container. Never, ever use vinegar (or any other acidic cleaner) or TSP(TriSodiumPhosphate). White vinegar can be used to wipe water spots off plumbing trim and shower doors, but when used on grout it will strip your grout sealer, then remove a microthin layer of grout and make the remaining grout more porous and prone to dirt. Vinegar is a mild acid and cementitious grout is alkaline, so the acid attacks the alkalinity in a quieter form of the old vinegar and baking soda experiment.
Every two years or so, or whenever you notice your grout darkening when wet, you should clean and thoroughly dry your shower and seal the grout lines with a high quality penetrating grout sealer. StoneTech™ and Aqua Mix™ both make excellent sealers and can easily be found online.
To seal your grout, pour a very small amount (1/8") of sealer into a short plastic container and use a 1" foam brush to paint the grout lines in about a 2'x2' area. Only dip the very tip of the foam brush in the sealer. If your brush gets too much sealer in it things will become messy quickly. After sealing your 2'x2' area, rub the area briskly with a clean cotton rag or handful of paper towels, changing sides frequently.
Ceramic Tile/ Epoxy Grout:
You can use almost any household cleaner you wish, even the motorized spray type that contains a mild form of citric acid. Epoxy grouts hold up much better to chemicals, acids, and bases. The safest course is always to use a PH Neutral cleaner unless it's ineffective, then try something a little stronger.
Solid surface materials such as Swanstone™ are some of the most impervious materials that can be used in a shower, and can be cleaned with almost any household cleaner with the exception of blue window spray cleaners. (They won't hurt your Swanstone™ but they'll tint your caulking blue.) If necessary, Swanstone™ can be cleaned with abrasive cleansers and green pads. One of the great advantages of a Swanstone™ shower, besides its long life, is that if you should decide to sell your house sometime in the future, you can spend an hour cleaning your shower and bring it back to a like new condition.
Rick Anderson- Cell 317.513.3715