In our tanks, O. struma successfully adapted to the manmade
habitat. The grass was planted to block the sunlight. Remnants of food
contaminated the substratum of soil, and the earthworms Perinereis
aibuhitensis grazed on the remnants of food and detritus to alleviate
the speed and extent of contamination. Caves of the crabs, which got
along well with Onchidium during the experiment, provided a better
habitat during the daytime and hibernation.