Review on Optimal Pond Water Conditioner - Seachem Pond Prime by Amanda Estrada

I used to use Pond Prime but the current online retailer I use [WWG] doesn't offer it. Pond Prime has the benefit of 'neutralizing' ammonia and removing chlorine and chloramine from tap water. I get ammonia spikes when my koi spawn, so instead of looking for a second one to solve my ammonia problem, I searched the internet for another source of Pond Prime to use a water treatment product. Went with the cheapest seller and when the item arrived the front tag was missing. Oh oh! It is a fake? Anyone who has used Pond Prime will recognize the smell right away: A VERY strong smell of sulfur. It definitely worked and seems to have worked - the chlorine level stayed at zero after a partial water change and the ammonia level dropped from over 2ppm to 0.5ppm in 3 days [test reagents measured ALL ammonia as NH3 and NH4+]. However, the missing label worries me and I will contact the seller to find out what is wrong.