I used Kent for a lot of years, and it is good. But I had to dose more with it, so as long as you don't mind that. It's all good. I switch Reef Crystals about a couple of years ago when I up graded to a bigger tank. A lot less dosing, but I hated after making a fresh batch to do a water change the brown crap in my trash can. I know a maintenance company that uses the Red Sea Pro and swears by it. The took care of my tank for a few months and my corals looked awesome. So I just ran out of Reef Crystals and Red Sea is at a good price now so I made the switch. The stuff mixes nice and no brown crap.