My Lawnmower was not a fan of my Sleeper Goby. Tormented him constantly, so the Lawnmower was given away. No more stress in my 34g now.
That said, I added a Bicolor Blenny, to my 34g and the two are absolutely fine together. I see much less aggression from the smaller Blennies than I do from the larger ones. My Starry Blenny rules my 75g.