My UDS runs straight and true at 270*. This is with all intakes closed and 2 1" exit vents open. I love this temp for my brisket and butts. I would like to get the temp down to around 220-225* for ribs/fish.
My process was/is fill my charcoal basket and mix in some chunks then add a full chimney to that. Talking to some other guys they are saying a full chimney is too much and try 1/2 chimney.
So am going to do that in morning but was also considering the water pan idea. Always open up an intake if needed to bring temp up.