Yes mate that size is good, a pair would be ideal, what people are doing is buying a group and hopefully obtaining a pair and rehoming maybe selling the other's. They live in harmony until they start to mature, then they start squabbling, then it gets a bit worse, once a pair seems to have formed you remove the rest quick smart
Both my ornatipinnis's and sp assam's did the same, i rehomed the 3rd ornatipinnis, the other female sp assam is now in my larger community tank, I found the ornatipinnis's to be funny with tank mate's but this was when there was three, but most people who keep them say there aggresive with other's and highly reccomend a species tank,
There's no easier fish to care for in my oppinion, They need minimul waterchange's and eat almost anything, like prawn's/mealworms<dried and fresh/blood wom live.
no need for a heater as this perticular specie's is sub tropical, Set tank with either plastic or real plant's/bogwood/rock's and floating plant like duckweed, which i will send some if people buy the babie's, it grow's like wild fire, need to remove some from time to time so they can acsess suface as they are labrynth<meaning they breath from the surface.....
I may also have a group of four pulchra for sale if intrested, If i can't get another tank soon will advertise them aswell, there around 3inches, another beauty, same as the ornatipinnis's but small spot's on the face's instead of the larger you see on the ornate's