Any Coastal Reefers using natural sea water?

[Aquattro]

Ken, I've found that due to fw runoff, much of our costal waters around the Island have reduced values of SG, pH and Ca. And even if the levels were fine, you'd still consume them at the same rate as artificial sea water. Dosing, if you need to, will be the same.
The other side is pollution, dying plankton and possibly other contaminants. For the cost of an average water change, I prefer to stick to IO salt prepped in RO water. This way I know where I stand(recent bad salt aside).