I have a Valentini as well and he has become my absolute favorite! I love checking in on him at night, when he's all cuddled up on his favorite rock
Mine likes snails as well, but he's only had a taste of saltwater snails so far. I've been hesitant to put pond snails in the tank... I'd also suggest feeding raw clams, mussells, shrimp (with shell), heck even crab or lobster! (Our fish eat better than we do at times, eh?) I found some frozen mussell cubes that 'Diddy just loves. I thaw half a cube with some garlic and he goes nuts. He also likes Emerald Entree, so I'd suggest that, too.
Post more pics! I love Valentini pics

This is not a "hobby." It is a life-style.