Adding Water?

I stick mostly to 1-2.5 gallon batches and often struggle to hit post boil volumes. Seen many places recommending simply adding water straight into primary before pitching yeast but it seems like that waters down the beer.

Would it be better to simply stick with the existing volumes and have less beer?

I like to get the most out of my batches so I typically top it off with more water. But at the same time to avoid diluting my beer I'll calculate how much I displace and take that into account in terms of gravity for my next brew.

It also depends how much you're missing your volumes by to how much it'll be diluted. By that I mean since you're doing small batches adding .25 gallons isn't going to change your gravity much, but if you're coming up short 1 gallon then yea you'll see a significant change in your final gravity after topping off.

Make sure to boil that water before adding it into fermentor too. You wouldn't want to get an infection from your water source. I have heard that some water sources actually having bacteria in the water, nothing that would hurt a human, but gave the finished product a funky taste.

Input is very much appreciated! Made a 1 gallon IPA recently that needed a few cups of water. Made several other beginner all grain mistakes but it tastes like a Lager IPA.

I worry more about hitting my OG than having a certain volume, and this can be figured out through straight algebra. Measured Gravity x Volume = Desired Gravity x Volume.

For example, say you wanted an IPA with an OG of 1.065, but you wound up with two gallons at 1.075. To hit your intended OG (1.065), you would need to add .31 gallons.

Here's the math: 75 (from 1.075) x 2 (gallons) = 65 (from 1.065) x Unkown Volume (gallons). 150 = 65 x Unknown volume. 2.31 = Unknown volume.

Since you already have two gallons, adding .31 gallons of boiled and cooled water would give you 2.31 gallons of 1.065 wort.

In regards to OG, it impacts where your FG winds up, and your FG impacts the overall balance of the beer.