We would like to recommend using Medium-Fine grind size coffee grounds to extract.
The Medium-Fine grind size is a staple grind size, with texture like table salt.
Fine grind size is acceptable, but not recommended. It is finer than table salt and it's typically the size of most pre-ground coffee.
Here are the reasons why we recommend Medium-Fine ground coffee.
- Easy to clean.
Fine grounds might block up the filter basket. However, coarser grounds would not have this problem, simply rinsing the filter basket would be super clean.
- Excellent coffee.
It won't require much effort to extract espresso with Medium-Fine grounds. However, using Fine grounds might require more pressure and time to brew.
How to ensure if we are using the right grind size?
Besides the coffee grounds shape, we could also judge from the machine working status. If we feel is very hard to pump, or even some water is leaking from the water chamber. Most likely the grind size is using very fine here and it stuck the filter basket caused the high pressure could not be released normally. In this situation, please avoiding keeping pumping. We recommend opening the lid to release the pressure then re-cover it and pump. Or changing into a coarser grind size.