Q&A for How to Clean an Acrylic Tub

In addition to the vinegar and baking soda, try to use half of a lemon to fight the water stains. Apply the lemon directly to the stains, and then rinse and dry the area with a clean cloth.

You can try other cleaning elements such as bleach, borax, or hydrogen peroxide. Refer to "How to Remove Bathroom Mold" for instructions on trying these alternate methods.

Have you tried the vinegar and baking soda mentioned in the beginning? If that doesn't work, you could try using them together, but dilute the vinegar with water first in the tub, then add the baking soda. They will foam like crazy, but are very effective for yellow stains. Mixed in a bucket, they will take hard scum off of shower doors, too.

Soak one or more cleaning rags in white vinegar. Then drape or wrap the rag around the area affected by mineral deposits. Leave the rags for an hour or more, adding more vinegar if necessary to keep the rags wet. When the mineral deposits have loosened up or dissolved, remove the rags and clean the area with a clean towel or sponge.