AQUARIUS SIGIL

Magic sigils are usually made out of several complex symbols or geometric figures each with its own special meaning or intent. The shapes you chose here work pretty well because they are similar to water which is the primary element associated with the goddess Aquarius (hence the prefix Aqua). The overall feel of the art is also appropriate, Aquarius is a sign which represents shyness gentleness patience and sensitivity, and the gentle powder blue Background with the white foreground adequately gives those feelings.
Your lines work well, and the idea of using Aquarius in a sigil is fairly original. The only concern I have is that your art lacks impact. This is probably because you have such a light blue under white which gives your picture a very low contrast. On top of that the foreground lines are very thin which makes it even less eye catching.
I believe that this is a cool idea and that it is pretty well executed, on the other hand you probably could have gone farther in terms of emphasizing the foreground. I hope my critique helps. I really do think its a cool idea!