Rules at a glance
- Free fishing
- Fly only
- Barbless
Water temperature for Marble Trout
Warm — slow23°C est.ideal 8–13°C
0°14°28°
How to fish it · for Marble Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Water at 22.6°C. This is the line where catch-and-release kills marble trout. Do not fish for them today.
Likely species
Caddisflies
Caddisflies- Net-spinning caddis (S. Europe)Most likelyLower confidence#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- GrannomAlso possible#14–16 · PupaPupa first, then dries as the adults come off.
- Satin sedgeAlso possibleLower confidence#12–14 · Egg-layingSkitter it at dusk — this one's fished, not dead-drifted.
Hatch timeline · todayPeak at 6pm
Hatch predictions
Today's headline hatch shown — see all 6 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
ModelledModerate confidence
Modelled from regional ecology — no survey or occurrence data for this water yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Marble Trout fly box
Permits & access
Permit required — see local rules.
- RD Tolmin
- Fly-only, barbless
- Upper 1km closed (breeding water).
What's coming
Plan ahead
5-day outlook
Water here around 23°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
Hudourniška pregrada na Beli Terrain map
The full read · show the working · for Marble Trout · confidence 90%
How the 10 is built — score × weight = contribution
Temperature7 × 28%2.0
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity57 × 12%6.8
Limiting factor: Water temperature (22.6°C) is outside Marble Trout's preferred range (8–13°C)= 52
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Nadižaproxy
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 8–13 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 1 March → 30 September
- Marble trout 1 April → 31 October
Related guides
Booking & contacts
Bela (Breginj)
Water temperature for Marble Trout
Warm — slow23°C est.ideal 8–13°C
0°14°28°
How to fish it · for Marble Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Water at 22.6°C. This is the line where catch-and-release kills marble trout. Do not fish for them today.
Likely species
Caddisflies
- Net-spinning caddis (S. Europe)Most likelyLower confidence#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- GrannomAlso possible#14–16 · PupaPupa first, then dries as the adults come off.
- Satin sedgeAlso possibleLower confidence#12–14 · Egg-layingSkitter it at dusk — this one's fished, not dead-drifted.
Hatch timeline · todayPeak at 6pm
Hatch predictions
Today's headline hatch shown — see all 6 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
ModelledModerate confidence
Modelled from regional ecology — no survey or occurrence data for this water yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Marble Trout fly box
Permits & access
Permit required — see local rules.
- RD Tolmin
- Fly-only, barbless
- Upper 1km closed (breeding water).
What's coming
Plan ahead
5-day outlook
Water here around 23°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
Hudourniška pregrada na Beli Terrain map
The full read · show the working · for Marble Trout · confidence 90%
How the 10 is built — score × weight = contribution
Temperature7 × 28%2.0
Flow60 × 22%13.2
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity57 × 12%6.8
Limiting factor: Water temperature (22.6°C) is outside Marble Trout's preferred range (8–13°C)= 52
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Nadižaproxy
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 8–13 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 1 March → 30 September
- Marble trout 1 April → 31 October
Related guides
Booking & contacts