How to make mini air tank | Diy air tank 

Yes

No, you need a much more fine regulation of the gas for that

In a pool

90 psi

@@viniciusdiniz7689 if you use a 2L bottle it can hold 150 psi but it will explode TRUST ME I LEARNED THE HARD WAY so I used 130 - 145 psi just don't drop it if you don't want to be deaf.