Here's a modular outletsystem for waterpumps in tanks. There are a few outlets available in stores but there are limited in when it comes to ustomizing them and also they are usally very expensive.
With my system you can use straights, elbows and crosses like you want. The straight pieces also allow you to adjust part of the outlet holes in different directions to optimize the water streams in your tank.
Check the steps where I describe a few special parts.
Note: The pieces are designed to fit together and stay together so you should think how you want them fitted before pressing them together.
Step 1: Pipe Adapters
There are a few pipe adapters. Those pieces are the start pieces for the system where you can attach the hose from your pump. The number in the filename is relfecting the inner pipe diameter they are designed for.
Step 2: The Air Water Pump
This piece is designed to be put as a starting piece to the outletsystem or just as a pump to move water. It's principal is based on the fact that if small air bubbles traval up a pipe they suck water along with them creating a sucktion and therefore pump water.
To use it add straight pipes on top of it and a air hose onto the small connector on the side. And that's it your pump is finished.
Step 3: All 3D Parts
Have fun chosing the ones you need for our outlet ;)