How to Troubleshoot Your Starter’s First Week

You’ve added your water and flour, stirred everything together, and tucked your dehydrated sourdough starter away to do its thing. You check it the next morning, then again that evening. Maybe there are a few tiny bubbles. Maybe the surface looks exactly the same as it did yesterday. And maybe you’re starting to wonder if you did something wrong.

First, take a breath! A dehydrated sourdough starter can take time to wake up, and a lack of bubbles or rising during the first week doesn’t automatically mean it has failed.

Rehydrating a dried starter is a little different from maintaining an established starter. The microorganisms need time, moisture, food, and the right environment to become active again. Some starters show signs of life quickly, while others need extra patience.

Before you throw in the towel and start over, let’s walk through six common issues that could be keeping your starter from bubbling, rising, or showing any obvious signs of life.

1. Check Your Water: Is It Chlorinated?

Water is one of the easiest things to overlook when troubleshooting a sluggish starter.

Many municipal water systems use chlorine or chloramine to disinfect drinking water. While these treatments help make our water safe to drink, they can inhibit the microorganisms that help a sourdough starter develop, particularly under some conditions.

What to try:

• Switch to filtered water or bottled spring water for your next few feedings.
• If you prefer tap water, know that leaving it uncovered may allow some free chlorine to dissipate. However, this does not reliably remove chloramine, which requires an appropriate treatment or filter.
• Avoid using water that is extremely cold or hot straight from the tap.

You don’t necessarily need to buy anything fancy. Filtered water is a simple troubleshooting step that can help eliminate one potential problem.

2. Check Your Flour: Not All Flours Behave the Same Way

Flour is more than just food for your starter. It provides nutrients and contributes microorganisms that help establish the starter’s microbial community.

If you’re using all-purpose flour and seeing very little activity, the type of flour you’re feeding may be worth reconsidering.

What to try:

• Use unbleached all-purpose flour as a reliable starting point.
• Try incorporating whole-wheat or rye flour into a feeding. These whole-grain flours provide additional nutrients and may help encourage activity.
• Make sure your flour is fresh and hasn’t been contaminated by moisture or pests.

You don’t have to switch your entire routine to rye flour or buy several specialty flours. Even replacing part of your usual flour with whole wheat or rye is a reasonable experiment.

One important note: different flours absorb water differently. A starter made with whole wheat or rye may look thicker or behave differently from one made with white flour. That doesn’t automatically mean something is wrong.

3. Check the Temperature: Your Starter Might Just Be Cold

Temperature can make a surprisingly big difference in sourdough fermentation.

If your kitchen is chilly, your starter may be working very slowly. This is especially common when the weather changes or your home is kept cool overnight.

For many starters, a consistent environment around 75–80°F is a helpful target during activation. Cooler temperatures generally slow activity, while excessive heat can damage the culture.

What to try:

• Move the jar to a consistently warm spot, away from drafts.
• Use a thermometer to check the temperature where the jar sits rather than guessing.
• Use lukewarm water for feedings, around 75–85°F, rather than cold water.
• Avoid hot water, which can damage the microorganisms you’re trying to revive.

A microwave or oven can sometimes seem like a convenient warm place, but be careful: never accidentally turn on the oven with your starter inside. An appliance with an unpredictable temperature can do more harm than good.

The goal isn’t to make your starter hot. It’s to give it a comfortable, consistent environment where fermentation can happen. My favorite fast read thermometer can be found here $10.

4. Use a Kitchen Scale: Equal Cups Are Not Equal Weights

This is one of the most important things to check, especially if you’re new to sourdough.

When a recipe calls for equal parts flour and water, it generally means equal weights, not equal measuring cups.

Here’s why:

• ¼ cup of water weighs approximately 59 grams.
• ¼ cup of all-purpose flour weighs roughly 30 grams, depending on how it’s measured.

That means using ¼ cup of each gives you nearly twice as much water by weight as flour. Your starter may become much thinner than intended, making it harder to trap gas and visibly rise.

What to try:

Use a digital kitchen scale and follow the feeding ratio provided with your dehydrated starter.

For example, if your instructions call for equal weights of flour and water, you would measure 30 grams of flour and 30 grams of water—not ¼ cup of each.

If you’re feeding an existing starter, remember that a 1:1:1 feeding ratio means equal weights of starter, flour, and water.

A scale removes a lot of the guesswork and helps you keep your feedings consistent. You don’t need an expensive one; a basic digital kitchen scale will do. Here is one under $7

5. Check Your Jar: Covered, But Not Sealed

Your starter needs protection from dust and unwanted visitors, but it shouldn’t be sealed in an airtight container during fermentation.

As your starter becomes active, it produces gas. A tightly sealed jar can allow pressure to build up, which is something you want to avoid.

What to try:

• Use a clean glass jar with plenty of room for the starter to expand.
• Cover it loosely with a lid, or use another suitable breathable cover that keeps out debris.
• Don’t screw the lid on tightly.
• Leave enough headspace for the starter to rise without overflowing.

A loose cover also helps prevent the surface from drying out while allowing you to observe what is happening inside the jar. This is my favorite here.

6. Mark Your Starter’s Starting Level

Here’s a simple troubleshooting trick that can save you a lot of frustration: mark the level of your starter immediately after feeding it.

Sometimes a starter rises and falls before you happen to check it.

You might look at your jar in the morning and see a flat surface, then assume nothing happened overnight. But if the starter rose while you were sleeping and later collapsed, you may have missed the most important sign of activity.

What to try:

• Place a rubber band around the jar at the starter’s level immediately after feeding.
• Alternatively, use a piece of tape or a food-safe marker on the outside of the jar.
• Check for changes in height, bubbles along the sides, a domed surface, or residue above the current level.
• Take a quick photo after feeding and compare it with what you see several hours later.

If you see a tide mark or dried starter above the current level, that may be evidence that your starter rose and fell.

Marking the level is especially helpful once your starter begins to become active. It gives you a much clearer picture of its progress than looking at the surface alone. I honestly just use a stretched out hair tie 🙂

What If I’ve Checked Everything and My Starter Still Won’t Rise?

Don’t give up just yet!

A newly rehydrated starter may need longer than seven days to become consistently active. The first week is not a hard deadline, and some starters go through periods of visible activity followed by a few quiet days.

Here’s what I recommend:

1. Go back to the activation instructions that came with your starter. Different dried starters may have different rehydration and feeding schedules.
2. Choose consistent conditions. Use filtered water, a suitable flour, accurate measurements by weight, and a comfortably warm location.
3. Follow the recommended feeding schedule. Avoid adding extra feedings or repeatedly discarding large amounts in an attempt to force activity.
4. Keep observing. Look for small bubbles, changes in texture, a pleasant tangy or fermented smell, and any rise or fall in the jar.
5. Give it a few more days. If the starter looks and smells normal, a quiet first week alone isn’t a reason to throw it away.

If the starter remains completely inactive after an extended period of consistent care, revisit the instructions from the supplier and consider contacting them for advice.

One important safety note: If you see fuzzy mold or pink or orange discoloration, discard the starter rather than trying to rescue it.

A Final Word: Patience Is Part of Sourdough

Sourdough has a way of teaching us that not everything happens on our preferred schedule.

A dehydrated starter has to rehydrate and reestablish its microbial activity before it becomes a reliable leavening culture. It may take a little time, and progress isn’t always obvious at first.

Before assuming your starter has failed, check your water, flour, temperature, measurements, cover, and starting level. These simple adjustments can help you identify potential problems without changing everything at once.

And remember: bubbles are encouraging, but a starter that can reliably rise after feeding is a better indication that it’s ready to bake with.

If you’re still waiting for that first rise, give your starter a little more time. Your first/next loaf may be closer than you think!