Why building this farm.

  This farm was designed to produce a large amount of tropical fish in a bucket to feed axolotls. Using this farm, you could get the super rare dark blue axolotl in no time (1/1200 chance when reproducing axolotls).

Download.

  Use the Direct map download to get the world save. (file too large to be uploaded)
  Using the alternative download, you get the worldsave and a schematic to easily build the farm in your own world using litematica.

Where to build.

  If you target tropical fishes, you should aim for a warm/lukewarm/deep lukewarm ocean. The farm should be built at a certain Y level. Use the world save as a reference. Otherwise, align the schematic at Y = 63. The cyan stained-glass cylinder should overshoot the water level by 2 blocks.
  I have not tested it but you can also place it in a lush cave biome. Be sure the tanks are fully inside the biome and that there is no other place where the fishes can spawn.

How to operate.

  Be sure empty water buckets are placed inside of the chests on the roof. A redstone lamp indicates when there is not a lot of buckets left.

This farm has a built-in shulker loader attached. You don’t need to absolutely fill the corresponding chest with empty shulker boxes as the tropical fish in a bucket will flow directly into the storage system if no box is available.

To start the farm, right click on the note block. The light should turn on. Water buckets are dispensed inside the capture room while moving the fishes. You just need to stand close to the chain while aiming the centre of the water source in front of you (hold sneak to enter the room). Then, just periodically push the drop key while maintaining the right click of your mouse. This can be done automatically using macros. Fishes are caught in the buckets, then dropped on the ground to be processed. Water buckets are separated from tropical fish to loop back into the system thanks to an ally sorter. Do not worry if some fishes stay in the water source sometimes as they will be pushed at your aiming position by other fishes later on.


Signs explain everything there is to know to operate the farm.

How to stop the farm.

  Simply walk out of the capture room and turn off the system using the note block. You can come back into the room to collect the remaining water buckets. Place them in the water bucket buffer at the top of the build to avoid wasting iron.

You may collect the tropical fish in a bucket inside the storage room after that. Please note that there is a delay between the time when a bucket is dropped and when it is available in storage due to the allay filtering. This is why the filter’s clock is always on.

Working principle and some details.

  The capture room is built so that the player won’t release any of his catch thanks to the waterlogged chain. This chain, combined with the daylight sensors also prevent the fishes from escaping. An axolotl is placed to angry the pufferfishes so that they inflate and increase their hitbox size. Without this axolotl, pufferfishes may escape due to their small hitbox and kill the player. Waterlogged stairs are place so that filling an empty bucket won’t stop the farm in case of a lag. The second chain is to prevent the dropped items to get inside the water column. Items are collected by a hopper under the slabs. The slabs are added so that the player can aim at the fishes. The player is fully protected from uninvited guest such as phantoms thanks to the door.

  The allay filtering is large to enable the player to quickly capture the fishes (small delay between drop key inputs). 8 allays are placed to filter the water buckets from the desired ones. To place the allay, simply lure them using an item. You can remove the iron bars and place them back later on. After luring an allay, replace its held item by a water bucket by aiming the air gap offered by the iron bar.



PS : Because of a small change in minecraft 1.20 the water buckets are emptied when clicking on the glass block at the back of the capture room. This can be fixed by replacing it with a shulker box oriented such that it cannot be opened. As the captured tropical fish are released when clicking on a fish, the optimal catching technique is: <right click> (try to capture fish) then <drop> (either a fish in a bucket or a water bucket).




I hope this farm will satisfy you. It was built and tested in my survival world.