The Holyrood minister also slammed the "negative, unfounded smears and attacks" on salmon farming that he said were sadly all too frequently reported in "our largely metropolitan press".
And he urged members of the fish farming community to let their friends, neighbours and peers know of both the value of the industry to rural areas and the advances it has made.
Ewing said: "It is my privilege and pleasure to open Aquaculture UK.
"I believe there are 2,400 registered delegates and 200 exhibitors, and that this therefore marks and demonstrates the growing success of the sector."
Ewing emphasised how important aquaculture was in sustaining communties that otherwise wouldn't survive, pointing out that it provided 12,000 jobs with higher-than-average wages.
He added: "I cannot think of a sector which is on the receiving end of so much undeserved, negative criticism whilst at the same time there is so little credit given for the demonstrable and proven success that you deliver."
He continued: "Today I am launching, together with [Marine Harvest Scotland managing director] Ben Hadfield, a frankly momentous document called the Fish Health Framework.
"It is a 10-year plan in order to grow sustainably the industry and to continue to deal with the challenges that you face.
"That plan will have seven working groups, and the industry and the government and the experts and science will work together to overcome further all of these challenges."
Ewing said many were already being overcome, with sea lice numbers in decline since 2013 and cleaner fish a "terrific success story".
He said: "The general public don't know that you have overcome many of these challenges, they don't know about the massive investment that has been put into meeting these challenges. It's about time that they did."
Ewing urged his audience to read the Fish Health Framework, now available on the Marine Scotland website, and also the Reported Versus Reality booklet published by Scotland's salmon farmers last week, which he said was an excellent document.
"I would like you to get hold of this, distribute it to your friends and neighbours and peers, to set out the reality of the success of this industry and start to counteract some of the negative, unfounded smears and attacks that sadly we see all too frequently reported in our largely metropolitan press."