Job
No size: it holds your target rate. Put the size in to have the seed run out with the paddock.
How much seed
Grass seed
Fodder crops
Bulk load
Hopper fills
Log the hectare counter each time the hopper runs empty. After every fill it works out what the seed left needs to sow, and what to set the controller to.
Finish the job
Unopened bags plus whatever's left in the hopper. Blank counts only the bags never put in. A quarter of a 25 kg bag is about 6 kg.
Too much seed, let it run heavy — leave this job out of seed flow.