His current control over the Elements was perfect control of up to ten Mana Spheres for Air and Earth Element. For Fire and Light, he had perfect control up to nine Mana Spheres, while for Spirit and Water, it was at eight. Lastly, he was at seven Mana Spheres for Dark Element.
He could handle 10 Mana Spheres for Fire Element, but his control wasn't perfect still, so he counted nine as his limit.
Since he couldn't overuse the Spirit Element, even if he could feel his limit had grown after taking the cure for Spirit Madness, that didn't mean he couldn't earn it again. It was a cure, not something that granted immunity in the end.
You can join my discord server. Link in the synopsis of the novel