Yep Tropic Marin are a keystone player for over 30 years in Europe, being myself from the UK I know first hand it is a product everyone carries, the salt is used widely especially. But irrelevant of that, for a company in this industry to be around since 1964 says something. Many others we know of are barely 10 years old.
"The first boxes of Tropic Marin synthetic sea salt left our factory in Germany near the end of 1964. The older and outdated standards in aquarium and reef keeping were soon broken by the revolutionary use of pharmaceutical grade raw materials and the inclusion of all of the natural trace elements found in the ocean. Additionally, the custom built manufacturing machinery producing a homogeneous mixture of salts and trace elements brought much of the progress and success now attributed to Tropic Marin sea salt. Tropic Marin’s reputation in the keeping and breeding of marine animals has made it one of the most used marine salts in the world."
http://www.tropic-marin.com/web/english/homepage.html
click on philosophy link