Elephant nose get 8-12 inches but i am pretty sure they grow slowly... Bigger ones tend to be pricey... Again, i am not really sure cause i have not PERSONALLY KEPT THEM. Hopefully somebody with more experiance can help u soon...
My friend has a Elephant nose and its 9 inches long at 3 years old (ish). When I go over to his house his Elephant is always sticking his nose in the gravel looking for food, they are cool looking but not for me. I have no idea about a trumpt.
I got an 18" Golden Clown Knife in a 210g with oscars, aro, FH, gar, RTC and chocolate cichlids. It bothers no one and no one has enough courage to bother the knife.