Dishwasher powder & tablets
This is a popular recipe, and for good reason. It's quick to make, uses simple ingredients, and works just as well as many commercial alternatives. It's really one recipe with two finishes: mix it as a powder for speed and simplicity, or press it into tablets when you want something pre-portioned.
The ingredients aren't just for the dishwasher either. They're handy for soaking tea towels, removing stains from mugs, cleaning pots and pans, and a range of other household tasks.
The recipe
Mix the dry ingredients thoroughly and store in a sealed jar.
If using essential oils, add a few drops to the jar and shake well to distribute. That's it.
Combine the dry ingredients in a mixing bowl, taking care not to inhale any dust. Add essential oils if using.
Slowly add water a little at a time until the mixture resembles damp sand. It should hold together when pressed, but not feel wet.
Press firmly into silicone moulds or ice cube trays.
Let dry for 1-2 hours, or until fully hardened, before removing and storing in an airtight container.
The Dish & Dishwasher Powder is ready to go straight out of the jar, so you can enjoy the same benefits while saving your ingredients for other recipes.
Shop Dish & Dishwasher Powder →How to use it
1 tablespoon (~25g)
Add to the detergent compartment. Don't overload, more isn't a better clean.
1 tablet
One tablet per load, straight into the detergent compartment.
For best results:
Good to know
How does this compare to commercial tablets?
Both will clean your dishes. The difference is everything around that core function. DIY dishwasher tablets are typically:
The cleaning outcome is similar; the system behind it is not.
Why are my tablets too soft or crumbly?
This usually comes down to water content. The mixture should feel like damp sand. Too much water can cause tablets to puff, crack or soften; too little can cause them to crumble.
If tablets do crumble, don't worry, the crumbs are still perfectly usable, and nothing needs to be wasted.
Can I use vinegar or citric acid with this?
Yes, but not in the same compartment. Vinegar and citric acid are acidic, and sodium percarbonate is alkaline, so combining them directly neutralises both. Use vinegar or a citric acid solution in the rinse aid compartment instead. This helps neutralise residue and improve glass clarity without interfering with the wash cycle.
Is this safe for septic or greywater?
This recipe is septic-safe. It doesn't contain phosphates, chlorine or synthetic fragrances. Greywater use is more nuanced: while the ingredients are biodegradable, they are alkaline, which may not be ideal for garden reuse. If greywater diversion is important to you, this is worth considering.
My dishes came out cloudy, what should I do?
Cloudiness is usually a sign of mineral residue rather than poor cleaning. Try:
Hot cycles generally give more reliable results than eco or short washes.
Must be kept away from children and pets. This can be dangerous if inhaled or consumed.
Why this works
| Ingredient | What it does |
|---|---|
| Washing soda (sodium carbonate) |
Main alkalinity agent. Softens water and breaks down grease, so the percarbonate has less to fight through to reach the actual stains. |
| Sodium percarbonate (oxygen bleach) |
Releases hydrogen peroxide in hot water to break down organic residue, stains and odours on dishes and inside the machine itself. |
| Coconut soap flakes (optional) |
A mild surfactant that helps lift grease. Optional here since most of the cleaning work is already done by the soda and percarbonate. |
Under Your Sink · teaching you the system, one recipe at a time.