I used it when setting up a 75 gallon tank. I had just purchased 83 pounds of (mostly cured live rock). My LFS highly recommended it.
I didn't use the metal-gone and try to get a full cycle in 24hours. However, my tank did cycle completely in 8 days----it was most of the way through the cycle in 4 days.
I like the product. I also helped the bacteria along. I threw in about 1 gallon of water and a cup of crushed aragonite from a 9 gallon (already cycled) nano. I also used ro/di water from the very start (this doesn't help the cycle but it did lower my algae blooms).
