Originally Posted by foibled
It's the opposite actually. Larger/more holes allow for more heat transfer.
I would avoid messing around with your hookah and bowl setups if all you want to do is restrict flow. The only thing I would do is add a diffuser if you haven't already. Water level doesn't make much of a difference on draw.
I'd recommend concentrating more on the hose so you don't affect how your hookah smokes as much, more so the draw only. Try using something that reduces the hole size of the mouth tip, like a male plastic tip or a piece of electrical tape over the hose tip end with a smaller hole poked in it.
Allready added a diffusor makes a tiny difference not much, like the water level, but every little helps.
I like the idea off the hose and electrical tape, the thing i noticed is i get more flavour with the smaller gadge hoses and thicker smoke, same went for when i had my AF hookah which had a slightly more restricted draw.
And when i use the razan the flavour is not as concentrated, and is faint, maybe i need to clean my hoses, but thats what i feel