Here are some after pictures of a concrete cistern. It cleaned up nice!
Before pictures of a concrete cistern that I cleaned.
The benefits are worth it! This is kind of a yuck photo, but you need to know what can really happen when your cistern is not cleaned.
Plastic cistern after lots of elbow grease! She shines after about 3 hours of cleaning.
Before pictures of a plastic cistern exposed to light. Green water!