hey, if you order it on-line at jlaqauctics.com you get 20% off. Hopefully you have a large enough order to kill the shipping, or maybe its time for Fellow Reefer extrordinaires in your area to do a group purchase
I used it and hmmm... an ounce of prevention might be worth a lb...
how do you know, its the same as some of us taking multi vitamins (to a degree, your gotta think if it is designed to kill off the bad bacteria, how much beneficial bacteria that many corals need to synthesize their food is getting wasted in the process...
...but all my corals flourished for a significant period of time A.D. (After Dipping lol)
cheers