Overnight 1:6:6 Sourdough Starter Feeding Ratio to Build 400g (12 - 16 hrs Peak Window)
High-dilution overnight levain math to build 400g of sweet, de-acidified starter (100% Liquid) with zero morning collapse.
A 1:6:6 refresh for 400g splits the jar into 13 equal units of 30.8g — 31g ripe seed, 185g fresh flour, 184g water. Those three weights total exactly 400g, and the culture reaches a full dome in 12 - 16 hrs at 75°F. Building 420g instead (32g / 194g / 194g) leaves the 20g jar reserve so nothing is ever thrown away. Best for: Warm summer overnight build (77°F–79°F).
- Exact 400g Build
- 31g : 185g : 184gStarter : Flour : Water (1:6:6)
- 400g + 20g Jar Reserve
- 32g : 194g : 194gBuilds 420g total (0g discard waste)
- Estimated Peak Window
- 12 - 16 hrsAt 74°F–76°F (23.5°C–24.5°C)
- Levain Hydration
- 100%Warm summer overnight build (77°F–79°F)
400g 1:6:6 Feeding Neighbourhood: Seed, Flour, Water & Peak Window
Every row recalculates the 1:6:6 ratio from scratch so the seed, flour and water columns stay internally consistent.
| Levain Yield to Build | Seed Culture (1 Part) | Added Flour (6 Parts) | Added Water (6 Parts) | Ripening Window at 75°F |
|---|---|---|---|---|
| 1:6:6 @ 380g [Baseline] | starter 29g / flour 175g | water 176g | hydration 100% Liquid | 12 - 16 hrs at 75°F |
| 1:6:6 @ 400g Trimmed Read | starter 31g / flour 185g | water 184g | hydration 100% Liquid | 12 - 16 hrs at 75°F |
| 1:6:6 @ 420g Extended Read | starter 32g / flour 194g | water 194g | hydration 100% Liquid | 12 - 16 hrs at 75°F |
| 1:6:6 @ 390g Compact Read | starter 30g / flour 180g | water 180g | hydration 100% Liquid | 12 - 16 hrs at 75°F |
| 1:6:6 @ 410g Generous Read | starter 32g / flour 189g | water 189g | hydration 100% Liquid | 12 - 16 hrs at 75°F |
On-Bench Hydration & Fermentation Adjuster
Modify base flour mass, levain inoculation, or ambient kitchen temperature below to recalculate from this 31g : 185g : 184g baseline.
De-Acidifying Your Culture: Why High-Ratio 1:6:6 Feeds Maximize Oven Spring (400g Build)
Temperature and ratio interact. The 1:6:6 figure of 1:6:6 does not mean the same thing in a 68°F kitchen as in an 82°F one: with the 12 - 16 hrs window quoted at 75°F, a cooler room stretches it by roughly 3.8% per degree, so 185g of flour in a 100% Liquid refresh may need longer than the label implies.
If your culture is sluggish or smells sharply of vinegar, the ratio is usually not the culprit — the culture is. Two consecutive warm 1:6:6 refreshes, each feeding 185g of fresh flour against 31g of tired seed, strip out accumulated acetic acid and restore yeast vigour faster than any other single intervention.
Zero-Discard Scraping Method for 400g Levain (1:6:6)
- Divide 400 g by 13 Parts (30.8g Each): A 1:6:6 ratio has 13 parts, so each part of your 400 g target weighs 30.8g.
- Measure the 1 Seed Part (31g): That is your existing culture, weighed cold and fresh from the refrigerator.
- Measure the 6 Flour Part (185g) and 6 Water Part (184g): Add both, mix to a stiff paste, and cover the jar.
- Peak and Reserve (12 - 16 hrs): After 12 - 16 hrs at 75°F, portion out 400 g and keep the balance as tomorrow's seed.
Common Scaling & Troubleshooting Questions (31g : 185g : 184g)
Why is my 1:6:6 starter not doubling?
Usually the seed was neglected in the refrigerator. Two warm 1:2:2 refreshes at 76–78°F, each with 185g of fresh flour, will strip the acid and restart the yeast.
Does the 400g figure include the jar remnants?
No. 400g is the usable sourdough culture you take out of the jar; the jar build is 420g so that 20g of culture always survives the transfer.
Can I still make 400g if I only have 200g of starter?
Feed 200g of seed with 185g flour and 184g water, then treat the resulting 569g of sourdough culture as your starter instead.