You may have noticed something interesting when studying AeroPress competition recipes.
Some successful recipes use water around 100–130 ppm.
That can easily lead to a conclusion:
Higher TDS must make better AeroPress coffee.
But the competition evidence does not support that conclusion.
Look at the recipes
Different successful competitors have used different water profiles.
Some use relatively low-mineral water.
Others use substantially more mineralised water.
This variation is important.
If one number were universally superior, we would expect successful recipes to converge around it.
They don't.
So why does 100–130 ppm appear?
There are several possible explanations.
The brewer may prefer the sensory expression produced by that water.
The mineral composition may complement the coffee.
The water may interact well with the particular brewing recipe.
Or the TDS may simply be a consequence of the chosen mineral profile rather than the primary target.
We cannot determine causation from a recipe alone.
TDS is not composition
A 120 ppm water can be made in many different ways.
The water could contain different proportions of:
calcium
magnesium
sodium
bicarbonate
chloride
sulfate
and other ions.
So:
120 ppm
doesn't describe the complete water.
It describes one measurement.
What if the water is 60 ppm?
A lower-TDS water can also produce an excellent cup.
The 2025 World AeroPress Championship recipes demonstrate meaningful variation in water mineralisation.
That makes the idea of a universal competition TDS difficult to defend.
What should competitors actually do?
Start with your coffee.
Build a baseline water.
Then compare different profiles.
For example:
low mineralisation
medium mineralisation
higher mineralisation
Keep the brewing recipe constant.
Taste blind.
Record what changes.
Don't assume more is better
More minerals can change the brewing environment.
But more is not automatically better.
More calcium doesn't guarantee more body.
More magnesium doesn't guarantee more extraction.
More TDS doesn't guarantee more sweetness.
These are hypotheses to test.
A better question
Instead of asking:
"Is 120 ppm better than 60 ppm?"
ask:
"What does changing the water from 60 to 120 ppm do to this coffee?"
That question can actually be tested.
The Water Artist
Competition recipes are evidence that water matters.
They are not evidence of one perfect TDS.
Don't chase the number.
Understand the composition.
Then taste.
Water is the canvas.
You're the artist.