Ok, now we're under the gun. My wife and I, after extensive poring over the Web and taking polls of catalogs and shop owners still can't decide upon which salt will be the one to use. One owner swears by Instant Ocean which he has used for years without problem, another location uses Tropic marine - again for years - again without problem! Yet "survey says" Forty Fathoms - Marine Mix is the only way to go. I'm beginning to think that I should be looking for a used car - it might be easier! I know that its important that metals be low and particles should be dry and of uniform size but what is the salt of choice with experienced reef keepers? Does it really depend on how you mix and the quality of the water used???