This is an indoor aquaponics setup that I am using as a biofilter for my goldfish. I was spending around $5.00 each week to replace the charcoal filters and was tired of maintaining the filters, replacing water, and cleaning each week. This setup has been running for 3 months and the water has stayed clean. Once a month, I will clean the glass so people can get a clear view, but it really isn't necessary. I'm very happy with the results and get fresh lettuce too!