Ratio Questions For Grain Bags

Im getting 2 grain bags (2.25-2.5lb per bag) and I have some questions about ratios

  • how many CC's of spore syringe to use per bag? -how much coco coir and water? -what size tub?

In the past I've used 2 1lb bags of grain per 650g of Coco coir and 3qt of water in a 20qt tub which worked fine. But since I ordered different sized bags I'm wondering what I should change