Agreed. Fill the carto as you normally would for the first fill after you've punched it and screwed it in (one punch is all you need) then fill the tank and just refill the tank only as needed.
The white carto cap helps seal it 100%. You can leave it off but it is better to have it. I haven't had any tight draw issues on my PV. Try unscrewing it a little to improve air flow.
The white carto cap helps seal it 100%. You can leave it off but it is better to have it. I haven't had any tight draw issues on my PV. Try unscrewing it a little to improve air flow.