There was such promise in this show that it's a crying shame it got wasted. The first episode had problems, most notably with an incredibly unconvincing Shelley Hack, but most of the first season was watchable. Some aspects of the show were derivative, like supply officer Krieg, who recalled Tony Curtis' similarly creative officer from the "Operation Petticoat" movie. But the show had its heart in the right place. It did more exploring in that first season than the entire four year run of "Enterprise," despite the producers of the latter show claiming they would focus on exploration. Right up until the last episode of the first season, it tried to bring home the majesty of the oceans.
The second season was a whole different matter. Aside from the sudden emphasis on action rather than science, there were large problems with continuity and casting. Where the first season's "Abalon" episode made water-breathing humans a unique experiment, all of a sudden, there were a number of water-breathing Daggers from years before. The cast suddenly skewed young with the addition of Henderson, Brody, Dr. Smith and the DeLuise boys.
Season 3 found it even more off course. Suddenly the SeaQuest with the biological coating that shouldn't be exposed to air was found in a cornfield. The show gained a militaristic bent. It became everything season 1 wasn't.
Unfortunately, SeaQuest went head to head with the eminently forgettable "Lois & Clark" on Sunday nights, which split the sci-fi/fantasy audience. That fight to the death forced the producers to compromise in ways that killed the soul of the series. I can't even watch the second or third seasons anymore. They only remind me of what went horribly wrong.