Hi , I have a 55 gal tank.80 lbs. of rock with about 2 to 3 in of crushed coral..i have a mandarine green gobi,,can i put a rock crawling blenny in there to?I know not to put 2 of the same kind.but sense they kinda alike I wouldn't want then to kill each other..Thank you
that tank is big enough to be fine. blennys are usually only aggressive to their own kind. and this tank is big enough for the both of them, you should be fine