yeah, i googled that eel before i made my earlier post and mentioned how they said it is rare.
true about lids and eels.....many a time u could find some dried up ones just underneath their tank at the fish shop.
what we would do is take a plastic fish bag and shove them around the plastic backstrip of the glass canopy where the water intake valve is.
other good escape artists are red crabs [small FW creatures] and octopus.
octopus being the worst because the only opening they need is just large enough for their beak to fit through.
a long time ago, we had 2 fish tanks side by side .... 1 tank with an octopus they other with just fish.
we kept finding fish missing each day.....we later found that smart lil' b@st@ard sneaking over and doing a lil' fishing there! lol