Heres an update:
My clown goby is terrified of the lawmower blennys. I haven't seen them fight or anything but when the clown goby (yellow citron) sees the lawmower he swims away in panick. Ive had him 4 years. Very peacful fish.
The two lawmower blennys fight. One of them gets close to the other, then violently whips the other or bites. Then he swims away and hides.
One of them was in the sump today. I put it back in the tank. They dont eat either, just hair algae. I suppose an early demise for the lawmower blennys. Maybe a couple of months if they dont start eating prepared foods.
I wouldnt buy another lawmower again.
The lawnmower blenny can actually defend himself. When my large tang swims by him too close hell bite my tang, but it doesnt bother my tang lol. I wonder if these are even lawmower blennys lol