Water hardness in Thermi
300 mg/L very hard
Tap water in Thermi is very hard: 300 mg/L (17.5 gpg · 16.8 °dH · 30 °fH).
Source: EDEYA labcheck – ΔΕΥΑ Θέρμης (2026) · data checked 2026-10-21
Municipal water utilities (DEYA) in Greece usually combine boreholes in limestone aquifers with reservoirs and springs. The reported hardness is 300.0 mg/L CaCO₃. Scale forms fast on heaters and fittings; a water softener is a common remedy.
Greek utilities report total hardness in mg/L CaCO₃.
Water data
| Total hardness | 300 mg/L |
|---|---|
| Utility | ΔΕΥΑ Θέρμης |
How Thermi compares
- Tap water in Thermi is 27 % harder than the median of the 134 cities we track in Greece (237 mg/L).
- By hardness it ranks 39 of 134 in Greece (1 = hardest); 71 % of these cities have softer water.
- In Central Macedonia it is number 24 of 47 cities; the regional median is 300 mg/L.
- Nearest city with clearly softer water: Nea Raidestos, 4 km away (222 mg/L).
- Nearest city with clearly harder water: Exochi, 9 km away (452 mg/L).
Ranking of the hardest and softest water in Greece →
What it means at home
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Thermi
| Brand | Setting for this water |
|---|---|
| Bosch | H05 |
| Miele | 17 °dH |
| AEG / Electrolux | 4 |
| Beko | 5th |
| Hoover | S3 |
| LG | H3 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Thermi water hard or soft?
It is very hard: 300 mg/L as CaCO₃ (17.5 gpg, 16.8 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Thermi safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. Greek utilities report total hardness in mg/L CaCO₃.
How many grains per gallon is Thermi water?
17.5 gpg, equal to 16.8 °dH, 30 °fH or 300 mg/L calcium carbonate.
What dishwasher salt setting should I use in Thermi?
For 300 mg/L (16.8 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Thermi?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: EDEYA labcheck – ΔΕΥΑ Θέρμης (2026). Method: figure published by the water supplier. EDEYA labcheck – ΔΕΥΑ Θέρμης · Outdated figure? Tell us