One of the most effective and environmentally friendly methods for a hygienically clean toilet is based on the combination of citric acid and baking soda (or washing soda). This mixture combats limescale, urine scale, and unpleasant odors without any harsh chemicals.

The natural power duo: Citric acid & baking soda
Ingredients needed:

3 tbsp citric acid (powder): Powerfully dissolves limescale and urine scale deposits.

2 tbsp baking soda: Neutralizes odors and has a gentle abrasive effect.

Toilet brush
Step-by-step instructions:

Sprinkle: First, add the citric acid and then the baking soda directly to the water in the toilet bowl.

Let it react: The two household ingredients react with each other and form an active foam that softens deep deposits.

Let it work: Let the mixture work for at least 20 to 30 minutes. For stubborn urine scale, overnight soaking is recommended.
… Scrub & Flush: Thoroughly clean the bowl and under the rim with a toilet brush. Then simply flush.

Tip for the rims: Dissolve 2 tablespoons of citric acid in 500 ml of warm water and pour the mixture into a spray bottle. Use this to spray and wipe the toilet seat, the outside, and the area directly under the rim.