Dirt does not always expose itself in a white bathtub right away. As the layer of dirt builds, however, a darker film will become apparent that changes the inside of your tub from white to dingy. When it comes to keeping your bathtub as close to its original color of white as possible, regular upkeep is crucial. Since bathtubs can be awkward to clean, let the cleaning products do most of the job with just a little help from you, instead of having to put a lot of physical effort into cleaning.
Fill a spray bottle with water and squeeze in several drops of degreasing dish soap. Shake to mix.
Spray down your entire bathtub and let the cleaning solution work in for about 10 minutes.
Use a soft scrub brush or a sponge to tackle that layer of filth on your tub. As you scrub, spray on more cleaning solution. Eventually, you should start to see the white color return.
Sprinkle baking soda all over the inside of the tub while it's still wet. This will create a mildly abrasive paste to use as a cleaning agent.
Get your soft scrub brush or sponge and continue scrubbing the surface of the tub. After some hard work and a little more baking soda and water, your bathtub should be white again.
Fill a bucket with water from the bathtub faucet and rinse down the sides of the tub.