Advise to print with 100% fill to lower buoyancy and smallest possible layer height (mine goes to 0,08 mm). Chose water resistant materials like ASA or ABS.
I may have overdone with supports here.
The author remixed this model.
I resized gaps to 3 cm so my red claw shrimp will fit in there and conjoined 5 copies of the same into an Olympic pattern.