mega trapped air

[extrememachine]

So I replaced my ek reservoir with one that fits, the water flows and pc turns on except there is a 17inch gap of trapped air and barely any liquid.
Been tossing and turning the pc nothing.
Is there a definitive solution?

 

[extrememachine]

I shall get some pictures, the trapped air is ridiculously long

 

[extrememachine]

Thanks for the replies, yes filled reservoir to 90% tossing turning, used a res that fits and I noticed a phenomenal difference.
The only issue I face now is some games are freezing on me.