Will 2 otos get lonely?

Yes. He loves it. As of yesterday, though, I noticed that he is eating brownish algae (?) on the walls of the tank and even on the heater. He seems happy. I am going to set up a quarantine tank tomorrow and get three more otos to keep him company. I also have two clay pots which I will seal the bottom hole with aquarium sealant so that they have a cave.
 
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