Salt

Nope. The only thing "wrong" with it is they don't sell it. Plenty of serious reefers use it with great success.

The first ploy to making a sale is convincing you that what you use is garbage if they don't carry it.

 

They are likely looking at the calcium level and the fact that it is lower than other mixes. As long as you're keeping your calcium where it needs to be then it doesn't matter what it is out of the gate.

I just bought a huge container of Sea Chem (300+ lbs for 1000 gallons+), but after I'm done with that I'm going back to regular, good old Instant Ocean. It has lower calcium than others, but is otherwise a pretty solid salt. One professional outfit I know uses it for all their tanks (both display and farms) and supplements with calcium and mag - considering the results they get, it looks like a good way to go. I'm already doing that otherwise so I think this is a better way for me to go and far less expensive than buying premium reef salt.

 

I use Reef Crystals. Its great it maintains my calcium, kh, and magnesium with out having to dose anything.

 

I was using instant ocean and just switched to red sea pro. It does dissolve more quickly. I would do some mag and calcium every other week is all. But I am just starting to get a heavier load of corals