interesting idea kinda diablo like fish mage, it could have an entire lore to all that fishness.
it was a bit confusing the direction the spells go which made it a bit harder to get used to .... having mouse control at the same time as arrows and space makes a bit hard to act quickly, as you have to move your hand from the arrows to the spacebar or from the mouse to the spacebar ...
there is a good game loop there and quite a lot of content and decent models.