- Thanks for the question! I think when choosing which size to go with (as with any other brew system design) you need to ask yourself what are the typical beers you brew (or plan to brew). Are they mostly 1060 and below, or are they normally higher than that? If the former, then I'd say the 5 gallon system will be a great fit, and for those times you do bigger beers, you can either split up the mash (a couple smaller, high-gravity mashes), or you can just add some DME at the end to reach your gravity. The challenges with brewing 5 gallon batches on the 10 gallon system are mostly around adjusting your recipes to work with the bigger equipment. You'll have a shallower mash bed so your wort clarity can suffer a bit, and your boil off rate with the larger 20 gallon pot will probably be more. So, at the end of the day the 10 gallon system was designed for 10 gallon batches; you can definitely do 5 gallon batches, but you'll need to tweak your recipes and process over several brews before you get the same results. Make sense?