Just got a couple buckets of the reef crystals through Petco for $39. The sale is buy 2 for 30% off, add the repeat order (you can cancel it after ordering) for an additional 35% off, and then in-store pick up for another 5-10% off!!
Looks like its the bucket of salt IO Reef Crystal now. Last month their Reef Crystal 200g boxes were $43 and 2 for 30% off plus repeat order brining it down to less than $20 a box. Used another email account and got 4 boxes for less than 80$
Great deal for the buckets if you can get the additional 10% online pickup