Starry blenny

I've had this blenny for over a month now, and slowly he seems to be not swimming much anymore and I rarely see him eat. He looks like he is just withering away. Is there anything I can do or I can feed him to get him back to good health?!

blennies can be really hard to keep because it can be hard to get them to transition to frozen foods. According to a recent article in Coral Magazine, count them eating frozen as a bonus and dont buy one expecting it, and for this reason they are now recommending blennies go in well established tanks with plenty of detritus for them to eat because they are detrivores.

But it sounds like your tank is plenty mature so there might some other issue.

What fish do you have? How are feeding? What are you feeding? Did you see him eat before you bought him at the store?
Let's see... I have 2 false percs, 6 blue green chromis, 2 bangaii cardinals, 1 pajama cardinal, 1 long-nose hawkfish, 1 orange spotted watchman goby, 1 pink spot watchman goby, 1 panda goby, a couple shrimp, 1 purple lobster, and plenty of snails and crabs.

We just moved this tank at the end of June, but didn't get this blenny until August sometime. I didn't see him eat at the pet store, but I saw him picking at algae around the tank and eating an occasional frozen brine shrimp or two. However, we grow our own brine shrimp and dt's and feed it to the tank on a regular basis and he would definitely eat then. One day he just seemed to stop. Sadly however, we woke up today to a dead fish. :( Sad day. I just wished I had realized this sooner.

Thanks for the help though, and maybe you can have info on future blennies to come.