While Otocinclus are capable of living alone in an aquarium, it’s not the recommended setup for these social creatures. Acclimating to a new environment can be significantly more stressful for a solitary Oto compared to being introduced as part of a group. In the wild, Otocinclus are found in groups that exhibit schooling behavior, and they are more comfortable and less stressed in similar settings in home aquariums.
Maintaining a minimum group of three to six Otos would be best in a suitable-sized aquarium, as this mirrors their natural habitat and promotes the overall well-being and longevity of each Oto.