Instruct: Classify the given Amazon review into its appropriate rating category
Query: Doesn't polish the water. Filters out bigger particles fine.

I used this for a 90 gallon fish tank. After I changed my previous filter media with this one the water became cloudy, and still, after 2 days is cloudy. I have cut to fit 6 pieces and placed them in my filter now. Waiting for new filter media from amazon now.