Well, the word docile in its context is completely in the eye of the beholder. I know I shouldn't but there are a few fish with one of my tesselatas ( biggest eel, along with green moray) and there are no problems for 11 months (which is when I introduced the other fish). Although the Tesselata is considered to be by most..The most aggressive eel there is.
A lot of people on here see the taboo/gossip around the tesses and spit it back out for other people as "understood information"
I have never had an "overly aggressive" eel. Tesselatas, and other eels deemed overly aggressive usually arises when fed (if in a community tank). If the eel has its food stolen from it, it will attack the robber.
One needs to learn how to feed the eel correctly, what to feed it, and when to feed it, and how often. This in time will lessen their aggressiveness. this technique can be done with all eels to make them less of a meany. In the VERY long time I have had my tesselatas I have NEVER had one eat a fish that it was not meant to eat.
I'm sorry this kinda rambles on and on so I will directly answer your questions.
The biggest eels are both the tesselata and the green moray, both can reach well over 8 feet in the wild and weigh as much as a small child.
the most "naturally docile" is the Snowflake eel, Although it is not NEARLY the size.
Here is a picture of one of my baby Tesselatas.
he is about 3 feet long 7lbs.
If you get one of these you will certainly need to upgrade to at least a 300g but will do fine for a year and a half (if fed well) in a 125.
