We need clarification here!
Congo puffers (tetraodon murius) are from Africa, bury themselves in the sand and look like potatoes.
They do best alone and grow upto six inches
Dwarf Puffers (carinotetraodon travancorius) are Asian, tiny, colourful and fast moving.
They like to be in small groups (but can be kept alone) and grow to around one inch
There's no such thing as a congo dwarf puffer, so which is it?
neither of these puffers do well with other species, so tankmates are limited to small plecs such as bristlenoses and rarely moving armoured catfish such as banjos and not much else.