A cleaner fish habitat support apparatus (1) for an aquaculture facility comprising a peripheral frame arrangement (5,7,51,59) defining a habitat support region (21) of substrates (19) for supporting aquatic flora, such as kelp (43), for use as cleaner fish habitat enables the reduction of ectoparasite attack on fish cultivated in an aquaculture system such marine fish farm cages (e.g. salmon farm cages) by providing a suitable habitat for ectoparasite removing cleaner fish, which can be adapted for raising and lowering to enable the apparatus to be positioned at different depths according to seasonal behaviour of cleaner fish and which creates a sheltered environment within the cage (25) more typical of the chosen habitat of cleaner fish in a natural marine environment and thereby extends duration of protection for cultivated fish against ectoparasite sea lice attack and lifespan of cleaner fish.
