Your bath tub can become quite dirty over time so keep in mind a few of these tips for effective and easy cleaning.
Rings in the Tub
To avoid bathtub rings, don't use oily beauty preparations in the bath. They leave a ring and also they make the interior of the tub very slippery and dangerous. Use a water softener if you live in a hard-water area; rinse the tub immediately after bathing. If a ring does form, wipe it off with a cloth dampened with white spirit. Wash oil immediately with a solution of washing up liquid and rinse several times. On plastic baths use undiluted washing up liquid.
Rust Rings
Often of you leave a metal can like shaving foam on the side of your bath, you will end up with a ring of rust from the base of the can. Well a simple idea to combat this problem is to cover the bottom of my shaving can with clear mailing tape.
Hard water stains
To get hard water stains off of the bottom of your tub, use a paste of vinegar and baking soda. Don't use this on fiberglass as the baking soda could scratch but on porcelain and cast iron tubs it is great!