massive mouth is correct. don't be fooled by their looks. the mouth is twice the size you think it is. BGK's do grow very large and will need a decent size tank, but they take a while to get there. mine is about 18cm and i have had him for about a year. he was approx 10cm when i got him. currently living in a 4ft tank with a clown knife, but this needs to change soon as he is starting to get aggressive towards it. he is also very good friends with the 28cm albino pleco in the tank
if you do get one, try to avoid feeding live foods as they will refuse any other once hooked :roll: