Wild carp (sazan) 97 cm

What the index is made of

The base of 69 points is set by the water temperature; the other factors shift it.

• +1Pressuresteady (0.2 hPa/3 h)Steady pressure is usually favourable according to anglers; studies have not confirmed it.
• +1Windweak, 4 km/hA light wind ripples the surface and brings food to the bank (anglers' experience).
• −3Cloud coverclear, 0%Strong midday sun scares fish; they stay deep and in the shade.
• −3Water clarity≈ 18 FNU, satellite 10 NovTurbid water: visibility drops and fish rely more on smell and vibrations, so try more conspicuous baits.
• −2ChlorophyllHigh chlorophyll, possible bloom, NDCI 0.11, satellite 10 NovPlenty of algae in the water; there may be less oxygen near the bottom.
• −2OvergrowthMarkedly overgrown, 35% of the area, satellite 10 NovVegetation narrows the open spots for fishing; look for clear windows and platforms.
• −2Water level from the satellite73% of the usual area, satellite 10 NovMarkedly lowered water level: fish retreat to depth and the banks are exposed.
• −2Invasive species nearbyPrussian carp, pumpkinseed, GBIFInvasive species displace native fish and occupy shallows. The score reduction is only small.
• −1Nitrogen in groundwater (SHMÚ)nitrates typically 0.5 mg/l (standard 50), ammonium above the standard at 1 of 5 stationsGroundwater reaches streams as base flow and carries nitrogen from fields and waste. Nitrates feed algae and contribute to nighttime oxygen crashes; nitrites are toxic to fish. Nitrites and ammonium can also be natural in deep groundwater, so at most one point is deducted for them. The data reliability is 85% (5 stations within 10 km, nearest 3.4 km, data from 2025), and the adjustment was applied in full.
• −2Harmful substances in groundwater (SHMÚ)metals and metalloids (above the standard at 2 of 5 stations), highest value 12 times the standardMetals, pesticides, PFAS and chlorinated solvents above the standard show the burden on the surroundings. The standards are set for drinking water and are stricter than the limits harmful to fish, so the reduction is small; metals can also come from rocks. PAHs are not counted in the score. Data reliability is 85% (5 stations within 10 km, the nearest 3.4 km, data from 2025); the adjustment was applied in full.
• −1Iron in groundwater (SHMÚ)iron typically 2.79 mg/l (standard 0.2)Dissolved iron precipitates when groundwater emerges into the air and clogs gills, gravel with eggs and invertebrate shelters. Data reliability is 85% (5 stations within 10 km, the nearest 3.4 km, data from 2025); the adjustment was applied in full.
• 0Aquatic insect hatches0.0× the average month, 0 of 25 observations in the year, iNaturalistAquatic insects are scarce this month; food near the bottom matters more.
• +1Water hardness≈ 13.8 °dH, ŠGÚDŠ atlasHarder water is more productive, has more food and buffers acidity swings better.