Oh, one more thing. Because this waterpart is not removable, i am making it so that i can disconnect the hose for the waterfall and connect another on to pump out the water into a bucket or something.
First, i lead the hose outside and put a connector on it, then a hose with another connector (male/female) will go back inside an to the waterfall. Let's show this in pictures
pump with hose (which goes to the outside) :
L-part going through the viv wall :
The outside hose, with the separate hose for pumping water out connected to it :
The other L-part, for the hose going to the waterfall :
The waterfall hose (still have to complete this, first testing how best to place it) :
Hope it's a bit clear on what it has to be(come)...