If you have newts in your pond does that mean the water is clean?

Possibly but it is a lot healthier for the insects fish and other sorts of nature living inside to produce more. my family started of with about 10 fish and in 3 years numbers have gone up rapidly.. we have about 200, and newts. Futhermore in the summer dragonflys come along as well as pond skaters. SO My opinion is the longer you leave the pond, the more naturally clean it gets :)