Utilization of aquacultural by-products in wastewater remediation is attractive because of the economic and environmental benefits that can be achieved. Within this paper, a blue mussel shell derived adsorbent, SC, was studied for the adsorptive removal of methylene blue and safranin-O dye from solution. When applied to methylene blue and safranin-O adsorption, the adsorption processes could be described by pseudo-second order rate kinetics and represented by Langmuir isotherms (i.e., monolayer adsorption). The adsorption capacities were 1.81 mg/g and 1.51 mg/g for MB and SO respectively. The behaviour of our SC material was comparable to other carbonate materials derived from the shells of different aquatic species, whose surface area and limited functionalities also led to relatively low maximum adsorptions being achieved.