We have a diamond goby and a lawnmower blenny. the lmb perches and waits to chase the goby every so often. if i could catch the lmb i would get rid of him but im not tearing my tank apart to do so. the goby doesnt show signs of stress(he sifts good, eats frozen, no ich) has made burrows for himself throughout the tank, so when a dive bomb happens, he flees to the nearest hole and opens his mouth huge. I would say they would be fine if the goby was added first and blenny second. we happened to do the reverse w/o knowing the potential of the blenny being a B*&%$ and going after the goby. both do an awesome job.
melly