Feminist scholarship has increasingly turned towards the ocean as a conceptual apparatus in which to think through the complex philosophical and ethical dilemmas of the Anthropocene. Responding to the ebbs, flows and transformations of the oceanic turn, our article outlines our interactions with four decorator crabs. It begins by situating our experience of thinking-with these crabs as a feminist practice of care within the conceptual context of the ocean. Our article then draws on the knowledge that arose out of our (...) fertile entanglements with the crabs to propose that: 1) the aquarium, with its colonial histories of subjugation, is a fertile space to re-image human–aquatic relationalities, revealing the fallacy of human control over ‘nature’ and emphasising the agency of marine worlds; 2) Stacy Alaimo’s concept of trans-corporeality is a powerful way to think through the consequences of an acidifying ocean, both for ourselves and for our shelled companions; and 3) remediation is a radical approach to taking seriously the materiality of watery worlds. The objective of the article is to craft a practice of material feminism that entangles our more-than-human bodies to learn-with decorator crabs. In doing so, we show that the aquarium is a potent space of transformation that allows us to imagine new and distinctly feminist entanglements that dismantle hierarchies. We show that thinking-with the materiality of marine worlds is a series of remediations, both material and discursive, that dissolve the boundaries between entities, creating an embodied environmental ethics that is necessary as a feminist challenge to the Anthropocene. (shrink)