So, I know my keet Tango needs different types of perches, different sizes, textures, etc...but what are the best? Obviously natural types, but what about the concrete ones that they say exercise the leg muscles? The sand / pumice ones that they can groom their beaks on, and their nails? Are those something I want for him? I know not to put gravel paper down because it's uncomfortable for the feet and can irritate them, so wouldn't the grooming perches be the same? Thanks!