Please note, I am trying to keep the question title and the first few lines of this question vague, because it's a major spoiler and if anyone else is like me and is just playing this game for the first time (yes, I'm way behind the times) I don't want to spoil it for them!
After I reach Phaaze and enter Hypermode permanently, I don't understand what to do to release Phazon, and as I continue to go deeper into the planet my Phazon bar just keeps filling up with more and more yellow, until I eventually die. It almost seems like firing charged shots and missiles increases the bar? I couldn't really tell from my one and only experience on Phaaze what to do to keep the yellow bar down.
How do I vent Phazon (and not die from corruption) in after reaching planet Phaaze?