The go to tank size for most paintball players is the 68ci 4500 Psi tank. These fit most people well, are not too heavy, not too long, and will usually get them through a point or a few games depending on your marker and how much paint you are shooting. These tanks are available in a variety of different manufacturers, with different regulators, and in a wide variety of designs. One important thing to note about this size tank is that 68/4500 tanks changed size recently, so if you used to play years ago, got back into it, and 68ci tanks don’t feel quite right, it is because they are in fact different.