He is probably almost 4 inches who knows it is a tiny lil baby. Doesn't show the cool coloration yet has some noticable indications of future colors and designs. The tire-track is peaceful I've had many types of eels and he leaves them all be and if he did get aggressive I'de make a division but I doubt that since hes never killed anything other than worms. Tank mates are tiretrack eel, peacock eel(never ever seen since the first time i got him he hides under sand the entire day even all night idk how its alive but it is), sailfin plecoman, lil bala shark, senegal bichir which is also fine with smaller things i've had shrimp before and nothing killed those so I think he'll be fine, but I'll watch them and set up precautions if anything in there decides to piss me off. Also got some plants I dont know the name of.