Why should greys be on high potency Harrison's?

[Featheredsamurai]

Kenji came with life time course, I'm ordering him another bag now. Harrison's always says African grays should always be on high potency. I'm not sure why though? Do they need more of something that other birds don't? I'm ordering him high potency, but I would love to understand why I am needed to do so.

 

[Featheredsamurai]

Wow! Your awesome thankyou soooo much! I've book marked the page so when I have more time I can read it all. That's the most helpful gray site I've seen so far