Carto size and tank size

[katandmouse]

Hope this makes sense. Here goes:

I haven't used a tank/carto setup before and I see on the site I'm shopping that there are different sizes in the tanks, 19mm and 25mm. I wanted to get the larger size 25mm in the hope it will hold more juice.
Now, I need to get the right carto to accompany this tank.

This is where I get confused.
Since this tank is a little larger than the 19mm I don't know if I need to get larger cartos i.e. the XL cartos or does this not matter.
.

 

[rolygate]

AFAIK all tank internal dimensions (the internal diameter or ID) are the same and fit a regular 9mm carto, except where they clearly state the tank is for some kind of XL carto.

However tank lengths are commonly different and you need to take note of that. Longer tanks won't fit shorter cartos.