Need help with Vaal Storm Call build

Hey everyone,

Been following a build from streamer/youtuber CuteDog and its amazing.
The idea behind the build is having a small mana pool just enough to kill 1 pack with storm call and futher chain the map with vaal storm call.

One thing I can't figure out though is how to get my mana pool big enough (or reserved mana small enough) to add grace to my active buffs.
Currently I have Herald of Ice and Wrath active but if I add Grace I don't have any mana left.

Edit: Woops, stupid me. Slotted in a lvl1 enlighten, not a lvl 2. Think I need lvl 3-4 to get the mana pool I want because lvl2 only gives 1 storm call. Good thing I'm lvling because that's going to take a while lol. Don't know if theres a workaround in the meantime.

Another question which I can't find an answer to is how do I get 5 charges on my Vaal Storm Call? Does it have to do with my gems not being 20 yet or do I have to slot in more reduced cost of vaal skills somewhere? Currently I'm at 4.

Still leveling and finetuning thought I'd ask here before I make any more changes. Been searching but can't find an answer anywhere so hoping someone could help :)

PoB: https://pastebin.com/E64dgxVf