heaters for small fish tanks
I have a male Betta fish in a 2 1/2 gallon tank. Can I add any other fish?
I have an air bubbler, the water maintains itself at about 70 degrees right now but I plan to get a small tank heater. I am most interested in getting a cleaner fish like a pleco, but I’ve toyed with adding some neon tetras to add interest. Just thinking outloud – I know our tank is pretty small and I am not interested in starting a killing spree for Henry! 
Plecos need 20 gallons plus depending on species (of which there are over 700), they are huge waste producers, they make far more mess than they “clean”!
Otocinclus are in the same family as Plecos, need to be kept in groups NOT singly and are easily startled, they’d seriously hurt themselves in a tiny 2.5g, I wouldn’t keep them in any less than 10-15 gallons.
Neons need to be in shoals of 6 or more, personally can be in no smaller than 12-15 gallons.
A Betta would kill a male Guppy.
Your out of luck with your tank, keep it Betta-only. Small shrimp would be eaten by the Betta and snails are too messy.
