Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: Very clear water

I have an external eheim filter which is supposed to be able to handle my 70 gal tank, but the water clarity was not as good as I'd like many times. Adding this filter, though I'd rather not have something so ugly in my tank, has worked wonders for the clarity. I put a power head on it and turned the flow to minimum.