No - really no need to worry about hot soil, many say for example Fox farms soil 's are hot - never found that true, even when using correct nutrient amounts - but if you feel your soil is "hot" just reduce your nutrient amounts. size of containers has nothing to do with hottness - large containers will give you a better yield. size of containers ? Generally if one states if soil is to hot ; it nutrient use. What type of soil are you using ? If really is to hot add top soil to your mixture