I have 4 parrots who share the 150 g with 3 severums and a pleco. all are very active, I agree you may want to add another parrot, but remember they grow to about 8"
when i got mine, it was also shy and hides inside the cave and scares to come out and eat, so i removed the cave. Right now its in a 75g with salvini, carpintis, red devil, flowerhorn, giant danios, pink convict, satan juripari, and it doesn't even approach the cave, always on the water surface waiting for food or searching under gravels.
