Bought some home brew glass and got this 3 gallon jar with plastic lid which has a threaded hole on top.

Has anyone used one of these?

What goes on the threaded hole? Is it a cap, or some kind of screw on airlock?

Thanks to the community who gave me some great feedback both here and in the Brewhalla support email. Over the past 2-3 weeks I fixed the custom water section and some android screen issues.

If you haven't checked out Brewhalla, please play around with it. The recipe creation is not like any other brew apps. Hops, malt, yeast are all entered by touch.

Every tool and calculator I've used over the years is in the "TOOLS" section.

Full water chemistry suite + inventory management + brew deck 2nd device brew timer/checklist

Here is the summary of the latest version:

BrewHalla update: saved water profiles, easier-to-read text, and an Android fix

• 💧 Save your local water: In Water → Source Water → Custom, enter your water report, name it (e.g. “Home Tap”) and save as many profiles as you like. Pick one as your default and it loads every time you open the app. Saved profiles also appear next to the presets (Balanced / Hoppy / Malty / Soft / Burton / Custom) and fill in your target water and recipe water card. They’re stored on your device, so they won’t carry over to a new phone yet.
• 📱 Android fix: On some phones the back/home/recents buttons were covering buttons at the bottom of popups. Popups now stop above the device buttons, and long ones still scroll.
• ⏱️ Brew Deck mini timer: When you step out of the Brew Deck with a timer running, the mini bar now sits at the bottom with “Back to Deck” clear of your phone’s buttons.
• 👀 Easier to read: Grey text across the app is now a brighter, softer off-white, so labels and hints are easier to read without glare at night.

Android users: if any button still gets covered, tell me your phone model and I’ll look into it.

📲 Play Store: https://play.google.com/store/apps/details?id=com.brewhalla.beer