kasturipurba, just a rough guess, not able to measure them correctly as they are usually hidden among the driftwood 

endlicheri - 12 inch
delhezi - 5 inch
senegalus - got 3 of them, 9 inch, 6 inch and 4 inch

They are all living in a 2.5 ft tank with Shirui sand as substrate. I hope is ok if they swallow it as the particles get kicked up easily when the endli moves around. 
Your collection is superb, bro!!  I want to keep my bichirs in empty tank like yours, but they keep dashing around nervously whenever I go near the tank.    How to make them lose their nervousness?

Also, my endli refuses to eat anything other than market prawns. It won't take any pellets. Even then, only recently it has started to eat since I got it about a month ago. Does your endli behave like this when you first got it?