Anyone keeping numerous Triggers and Volitan Lion, in a 40gal. tank (no matter the size of the fish) should be ashamed of themselves...that's rediculous.
I've kept Queen Triggers, Clown Triggers, Black Hawaiian Durgeons, and Blue Throat Triggers with the Volitan I used to have. Keep in mind that none of them were with the Lion for very long...and, the Volitan was 15" long and could have easily killed each Trigger, as they were all almost small enough to be eaten by the Lion, if he really wanted to.