Brewing small batches in larger system?

I'll just throw it out there…getting a 3-5 gallon aluminum pot for your kitchen to me is well worth it. It's nice to have a good sized stock pot in case your feeding a crowd for chili or lobster or whatever the case maybe. You can then use that as your kettle for small batches, maybe 2-3 gallon batch sizes (fermcap would be suggested). A round 5gal igloo cooler mash tun would be a good match with that kettle. I recently got an almost new igloo cooler off craigslist for $10. Then you just need to get a bulkhead and false bottom and get a bigger 8-10 gal pot to work as your Hot liquor tank and double as kettle for bigger batches (which maybe you do BIAB style). Just to create a lot of number of variations on a relatively small budget and keep things modular.

 

On a similar note to the above, if your plan is to brew a few 1 or 2 gallon batches before scaling to 5 gallons then even when you've moved up to the bigger batch for your normal brews, something like a 3 gallon PET carboy can be a fairly handy thing to have kicking around, assuming that space isn't a massive issue for you. It gives you options like bulk aging or wood aging part of your batch, doing a split batch with different yeasts or dry hops in each fermenter, doing smaller batches for stronger or more experimental recipes, or doing an extra 3 gallon batch in parallel with your main brew if you need a lot of beer in a hurry.

 

I have a few fermenters available: two large glass fermenters for my 5-gallon brews and two 3-gallon PET fermenters for smaller batches. The 3-gallon size can handle 2.5 gal with just enough headspace. I personally would not put any batch larger than that into one of them, having recently narrowly avoided a blow-out.