My Common Pl*co used to be th same way [ It was 3 months after I put him in the tank before I even got another glimpse at the bugger ]
I noticed that, since I put a very large floating plant in my aquarium, he has been coming out a noticable bit more..
Don't know if its coincidence, or if the reduced light to the bottom of the tank is making him bolder, Just putthing this out here for those who complain about not being able to see theirs.
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Thats a very nice pic, Your Rubberlip blends in perfectly with the driftwood!