Very cool idea and execution of three different variations of the same core gameplay, all feeling and playing differently in a way that makes them all worthwhile to try.
The colors used really paint a nice underwater mood.

I do feel like I cant wrap my head around the controls completely as I always loose half my fish simply trough being unable to keep them inside the screen with my two mouse buttons. Difficulty felt quite high, but that might be connected with my control confusion^^

Fun game ! I really like the controls ! Neat concept and nice pixel art ! 

Thanks for the feedback! I've added downloadable versions, which shouldn't start off laggy.

The lags quite a bit at the beginning, but otherwise fun game!