For me, urchin is good but is a bulldozer, keeps carry frag and knock down stuff lol. For sandbed- conch is very good; help turn sandbed nassirus snail- also good, help eats leftover food and turn sandbed hermit crab - good but keeps killing my snail for their shell exchange sally lightfoot crab- good at eating leftover food, also help himself to dying fish lol. its quite big actually, duno if will be threat to small fish emerald crab- good for bubble algae but heard they go rogue story, had one before never see them disturb coral lawnmower- good utility fish, all day munching on rock and sand for algae tangs and foxface - good utility fish for algae as well, but do be aware of tang aggression. Also ich magnet, need proper QT cerith snail - also good for sandbed starfish- i go for bristle star or serpent star for sandbed detritus eater. i personally avoid sand sifting fish or sand sifting starfish to protect my microfauna population. magarita snail - i think is very good snail, saw it took out tough to remove algae on glass turbo and trochus snail - also overall good snail but keep kena attack by my hermit cleaner shrimp - also good shrimp, they also spawn frequently in my tank providing fish with additional food. peppermint- good for apitasia but in high flow tank dont do well, be careful they look similar to camel back shrimp, camel back is not reef safe thats all i know from my own exp. hope it helps. happy reefing! Sent from Singapore Reef Club mobile app