I just bought a lawnmower blenny today and acclimated him and set him into the tank and he isnt really moving alot. He just stays in one place. Is that normal? Also he has a really fat belly. Is that normal too?
He is probably just getting adjusted to his new home. Our blenny didn't come out much at all for almost a week when we got him and even now he hides for hours at a time but then he will come out and be all over the place all day some days. The fat belly is actually a good thing IMO - a blenny can starve fairly quickly if there is not enough food and yours has obviously had plenty to eat lately!
I've had a Lanmower Blenny for quite some time. He is rather rotund and did hide quite a bit when first put into the tank. He is my favorite fish as he is out all the time cruising from rock to rock!