Gymnothorax Polyuranodon and Tile

[godsbane]

Seeking advice on the two "Freshwater" moray eels.

From what I see in this forum a number of people have successfully kept G.Poly in freshwater for years?
How about G.Tile?

I was under the impression that both species need saltwater to sustain them for long periods.

Thinking of adding these two to my moray only tank but wanna be sure.

 

[Aw3s0m3]

There are lakes where G. polyuranodon are thriving and breeding in pure fw. But all G. tiles are found in heavy brackish. I've kept them both and the G. poly grew and was happy and healthy in fw but my G. tile eventually started getting stressed and I slowly acclimated it to sw where it thrived

 

[godsbane]

Still looking for a G.Poly at the moment.
Have a G. Tile but it is really shy - barely see it when the lights are on.