Buy a box of wotofo x fibre from ebay, best cotton for this rta and perfect amount everytime.
You will need 3 bits of firebolt cotton. You can wick is twice with 3 bits if you pull it most of the way through.Nice one, I might do that.
I have some Vapefly Firebolt Cotton in the post alright. Not sure if they're the right size for it...
Looks like your missing a seal where the bottom of the glass sits.
Edit: actually looks like its there.
Have you tried the standard glass.
I dont think wicking is the problem here must be a seal or that glass causing a loss of vacuum.
You will need 3 bits of firebolt cotton. You can wick is twice with 3 bits if you pull it most of the way through.
I use two bits up top and 1 bit at the bottom. Hopefully you get it sorted soon.