We want to put in a spa or a hot tub. I thought they were one and the same until recently when we began to shop. What's the difference?

A - Hot tubs are wooden barrels and spas are fiberglass shells covered with acrylic or other plastic materials. But some hot tubs have acrylic liners and some spas are free-standing with wood skirts.Tubs and spas have other basic differences: maintenance, durability, operation and overall appearance.

Tubs have a rustic and natural appearance; they blend well with decks, gardens and patios. But they're harder to clean and maintain than spas because of the texture of the wood and the angles and corners that are typical in their design.

Spas present more design options than hot tubs and are available in a broad range of colors. Their hard, smooth surfaces make them easier to clean.

Support equipment and installations are similar, and both are available as complete free-standing packages or as separate components that require assembly.

And remember, most building departments will require a permit for installation. In any case be prepared for additional installation expense and maintenance costs.

Calculate the expense of at least one additional 110-volt electrical circuit (maybe 220). Make sure your electrical system can handle whatever is required. Your electrical bill can jump $50 a month and more.

Be prepared to chemically treat the water regularly. And check with local ordinances. Most communities require a lock on all gates.

Q - We read your very interesting and informative column and have followed the dialogue about cleaning plastic shower pans (and stalls). Here is a simple solution to this cleaning problem that we got from our son-in-law.

He recommended that we try "Scrub-Free," a Benckiser product available in supermarkets. It worked like magic. Squirt it on and the stains run off, really.

A - Our thanks to you, your son-in-law and Scrub Free. And a secial thanks to your daughter for marrying such a wonderful guy.