blah... i use NSW purely because of lower cost and little effort (as i live close to the beach) if i lived inland more, i'd use ASW. personally, i dont believe there is much difference between NSW and ASW. it's seawater no matter how you look at it (albeit slightly different compounds or potentially slightly higher nutrients/pollutants in NSW vs ASW. but if it's 1 ppm of motor oil in your nsw mix, that aint gonna kill nuttin' :lol: IMO if you have a decent skimmer, dont be too concerned)
Way up ASW and NSW as a cost/convenience thing, not "which one is better". to answer the original question 5, so long as your NSW source is RELIABLE AND TRUSTED, it will be fine. if you find there are too many risks involved, then use ASW. simple. do some testing first or contact the council for test results from samples they take (or whoever does it)