Does the entire 23x23 max size Blood Magic altar need to be chunkloaded or just the altar block itself?
As Tonalom has said, I normally only chunk load the blood delivery system and the altar itself, the exterior runes shouldn't need to be loaded if you are merely passively generating blood, or taking advantage of your blood network. If you are doing rituals that require the outside runes you're normally standing there so you are body loading the entirety anyway.