Jonathon,
You could stick with "insipid" in this context...or a somewhat impolite way of saying "not delicious". More polite is "owishiku nai". But in the case of kurage, my preference is "mazui".
You do not like seafood? That is a shame...some of the best in the world is in Japan. How about shrimp? Is that off the list? If not, someday try "tendon"...it is one of my favorites. And, when Winter hits, see if you can get one of your local compatriots to take you to a shrine during snow flurries and try "amazake" (sweet sake with the lees still in it). Very "whafuu" (evocative of the spirit of Japan). The best place, in my opinion, to do that, though, is in Kyoto at the Kyomizudera...
Well, enough non-scuba stuff...get you in trouble? Never!
Joewr...henna gaijin dayo