First thing first. make a fucking pellet hopper to feed and distribute over that large area if you cannot create a ducted distribution.
Second to the first, when you are making a smurfberry soup, you onlt need to create ONE VAT and have a fucking fan blowing the smurf spooge into the pipes.
third it would be easier to feed each one of the fuckers a pellet than gassing them all.
There's lots more but I don't work for free.