Bling brand cleaner is by far the best cleaner on the market. This 12 ounce version is designed for use with plastics and acrylics. Its anti-bacterial, environmentally friendly, and completely non-toxic! Plus it will get most pipes clean in 1 minute or less. This is the cleaner we all use and we always recommend.
For small pieces, just place the acrylic portion in a ziptop baggie, put a little cleaner in it, seal and shake for a minute. For larger items such as tobacco hookahs with acrylic bases, put some cleaner into the hookah, cover all the holes, and shake for one minute.