Follow the recipe without substituting ingredients
On the crafting table, the heart of the sea occupies the center, eight nautilus shells occupy the remaining eight cells. Official Mojang article confirms the recipe and action. The mere presence of a heart or an inactive block does not have an effect.
For the first frame, prepare 16 full Prismarine Blocks, Prismarine Bricks, Dark Prismarine, or Sea Lanterns. Steps and slabs do not replace them. Before assembly, save a path to air or a supply of underwater breathing.
Build the ring around a water-filled center
Local conductor center(0,0,0). The horizontal ring is located at y=0: x,z=−2…2, the cells where|x|=2 or|z|=2 are filled. The perimeter of 5×5 contains 16 cells, the inner 3×3 are not filled with a frame.
Place the conductor on a temporary support, then remove the support. There should be water in the volumex,y,z=−1…1, including the waterlogged state of the central block. A dry pocket or leaving hard support disturbs the area. Underwater nearby, check the conductor opening and the effect icon.
Expand the frame and test its range
The second ring 5×5 in the x=0 plane adds 14 new blocks: two cells are already occupied. The third in the z=0 plane adds 12. The full form contains 16+14+12=42 different blocks, not 48. All three rings have the same center.
Place underwater control marks along the work route and linger at each one: the residual time of the effect after leaving does not prove that it is being renewed here. Check the coverage before going on a long walk. The Conductor does not drain rooms or cancel elder guardian fatigue.
Good visibility under the effect is not equal to the measured light of the surface. Check base lighting separately.
The airlock and safe exit to the surface are built separately from the frame. Plan approach and shore.
