Issue Salt water mixes I've been in the hobby for 50 yrs. owned 2 retail fish stores, Started with Instant ocean moved on later to Reef crystals yrs later I have 3 salt tanks 75 gal 125 gal and 220 gal tanks goes without saying I use a lot of salt I've found if you store Reef crystals for more than 6 months parts crystalize and won't break down during mixing. I now use Pro-Reef by Tropic Marin and have been happy with it ever since corals luv this stuff. Just Sayin.