A batch can be scaled using the Edit Campaign Batches dialog or when you select the base recipe for a campaign, in the Select Recipe dialog.
When scaling a batch, you can not exceed the min or max limits of any one of the scalable parameters in the recipe. If the batch scale value causes a parameter to become greater or less than the max and min limits of that parameter, it is highlighted in red. You must manually change that parameter (thereby creating a custom formula) or change the batch scale value so the parameter remains within its limits.