here is a idea i was thinking on, basically water is pumped up in the pipes, goes into mid-air bucket as its filling up it pushes air out of a 1 way air valve and then the auto syphon which is in the mid air bucket is activated releasing water down in to the main fish tank.

basically if it works you can remove the pump

please leave comments, yes i know its a bit crap video, its my first one!

giv thumbs up if u like it