So I got the decanter of endless water recently and decided to get Ignus, problem is that whenever I talk to Nemelle she just says she can't answer my questions and eventually silences me.

I have the decanter identified so that it is called Decanter of Endless Water, so that is not the problem.

Yes and no. I have 3 saves, one before I accept the quest, one after I accepted the quest, and one after I turned in the quest (and I waited for her to arrive at Aelwyn before talking to her).
In all of them she wont give it to me. I'm thinking that I may need to get someone else to direct me to Nemelle...

Ah, no. Thank you. I had talked to Ignus' lover and then she told me about the power word and I didn't feel like going on a hunt for someone as there was no clue given, so I looked it up. >.>

It worked, thank you.

Had another problem in the process though, game kept crashing whenever I traveled from one area to another. FIxed that by running as admin though. =D

Now that is a miracle cure for many problems with newer OS :P
Have fun with Ignus... for a time ;)