green koi pond water

Question
Our pond is @1,000 gallons and 1 year old.  We have 7 koi and 4 plants.  Our ponds gets allot of sun.  I treat the pond once a week for string algae (we had a problem with string algae last year but seems under control this year.)  Our pond water is a pretty shade of green however, we are unable to see and enjoy our fish unless they are feeding.  Someone suggested dissolved rock salt but I am afraid to try.  What you suggest as the best solution to "clear" our water?

Answer
Nutrient control is the only real way to control water.  Get a comprehensive water test performed (16 or so parameters) and compare it to a list of algae causing nutrients.  Do whatever it is you need to do to decrease any of those abundant nutrients.