Keep HydroCalc free and ad-free.

Hi, I'm Marc, a hydroponics hobbyist from Leipzig. I build HydroCalc in my spare time and offer it free of charge.

It turns your target values into exact nutrient doses, from concentrated stock solutions all the way to your reservoir. It stays privacy-first: no tracking, no ads, and everything is hosted in the EU.

Keeping it free and ad-free costs a little every month for hosting and the database. If HydroCalc saves you time at the mixing table, a small tip helps me cover those costs and keep adding features.

Thank you for stopping by, and for any support.