My preferred products (and ones I use) from Kent are the Salt which has the best consistency, balance and long term results than IO (Lower supplement levels and issues with alk once in a while), Tropic Marin Pro (as good but too expensive), Oceanic (dfficult to balance Ca and Alk with balanced aditives) and Reef Crystals (too much like IO lathough better levels) All this salts I have tested tried and discarded.
Also IMO Kent has the best supplements for Calcium TurboCalcium (Calcium Chloride), Magnesium Tech-M Magnesium, Garlic Extract and Strontium & Molibdenum.
Everything else is either not necessary, redundant or there are some other better out there.