I have a Snowflake and a Barred Eel. Both about 12-13". I had 15" Snowflake. He was considerable fatter than the 13". And noticably bigger. Unfortunately I did not heed warnings about sealing the top of the tank adequately and now he is gone. He was very pretty. So I'm wondering how long before these grow. Am I correct that it will be years until they get 24"?