One redstone fish farm

AFK Fish Farm with only one Redstone!
Original design by Panda4994

In case you want to follow pictures instead of a video:


You only need these for the basics. You can decorate around it as you wish. Technically speaking, you only need 5 stone bricks (or whatever you use as a building block).
5 building blocks, 4 half slabs, 2 chests, 2 hoppers, 2 tripwire hooks, 1 string, 1 redstone, 1 noteblock, 1 iron door, 1 bucket of water, 1 fishing rod


Just place two chests down and feed a hopper into it.


Feed another hopper into the hopper. Place half slab, one on the ground, one on the hopper.


I placed a redstone on the open hopper so that I get a little hitbox that I can place stone bricks next to. However, if this step confuses you, just skip it and follow the picture to the next one. This is just a helpful trick and not necessary.


A little tricky to see here, but I placed two blocks next to the air block above the hopper.


I diagonally placed two more blocks on either side and attached tripwire hooks to both sides.


I placed a door on the ground while standing on the hopper. This should place the iron door flush against the hopper.


I placed a half slab on top of the door and then connected another half slab to it.


The finishing touches! Add a note block under the second half slab behind the door. Add water above the open hopper. Add string between the tripwire hooks. Place blocks on either side of the door and put one redstone dust on it. And all done!