Cheap salt vs. expensive salt for your reef tank - part 1

Reefing is an expensive hobby and half the battle is knowing where to spend your money on. There are many options for salt water mixes. So far, i've been using the regular instant ocean, the cheapest possible mix ($60 for 160 gallons of salt water). But i've always been tempted by the more expensive salt. Is the grass/Acropora greener on the other side ? I'll be doing a little anecdotal test by switching my tank to Tropic Marin pro salt, the most expensive salt at my LFS ($135 for 200 gallons). My main concern here is if my corals will look better / same / worst with the more expensive salt. I'll report back regularly as i slowly shift the tank from IO to TM..

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