Symptoms to Look For
Check if your shrimp are showing any of these symptoms. Symptoms are grouped by severity to help you assess the situation.
Early Warning
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Shrimp hiding more than usual before molt
Visual: Normal pre-molt behavior but watch for extended hiding
Moderate
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Shell appearing dull or slightly milky
Visual: Loss of normal glossy shell appearance
Severe
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Visible white band/ring around body between carapace (head) and abdomen (tail)
Visual: Clear white line circling the body, like a belt
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Shrimp appears to be 'splitting' in two sections
Visual: Gap visible between head and tail shell sections
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Affected shrimp becoming lethargic, not moving much
Visual: Staying in one place, may be on its side
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Multiple shrimp showing white lines over time
Visual: Pattern indicates tank-wide mineral deficiency
Does this match what you see? If your shrimp are showing multiple severe symptoms, act immediately. Early symptoms give you more time to correct the issue.
Possible Causes
Causes are listed by likelihood. Start with the most common causes and work your way down.
Low GH (Mineral Deficiency)
The primary cause of white ring is insufficient calcium and magnesium in the water. Shrimp need these minerals to form new shells during molting. Without them, the new shell is weak and the old shell cannot split properly.
Test GH with a liquid test kit. Neocaridina need GH 6-12, Caridina need GH 4-6. If using RO water without remineralizer, GH will be near 0.
Unstable Parameters / Sudden GH Drop
Even if GH is adequate, sudden drops can trigger premature molting before the shrimp is ready. This commonly occurs after large water changes with softer water.
Track GH before and after water changes. Did you recently change water source or forget to remineralize RO water?
Using Pure RO/DI Water Without Remineralizer
Reverse osmosis water has zero minerals. Using it without adding GH remineralizer (like Salty Shrimp) strips minerals from shrimp during molting.
Are you using RO water? Do you add remineralizer? What is your target GH when remineralizing?
Diet Lacking Calcium
Shrimp also absorb calcium from food. A diet without calcium-rich foods can contribute to molting problems, especially when water GH is borderline.
Review diet - are you providing calcium-rich foods like blanched spinach, kale, or calcium supplements?
Extremely High KH Relative to GH
Very high KH with low GH can interfere with mineral absorption. The ratio between GH and KH matters, not just the individual values.
Test both GH and KH. If KH is much higher than GH (e.g., KH 10 with GH 3), there may be absorption issues.
Solutions
Option 1: Emergency Response for Colony (Cannot Save Affected Shrimp)
Shrimp already showing white ring will die regardless of treatment - do not stress yourself trying to save them
- 1
Accept that affected shrimp cannot be saved
Once the white ring is visible, the shell has already failed to separate properly. The shrimp will die within hours to days. Focus entirely on saving the rest of your colony.
Do not attempt to 'help' the shrimp molt by manual intervention - this causes more harm
- 2
Test GH immediately
Use a liquid GH test kit (API GH Test Kit or similar). This is the most critical parameter to check. Write down your current GH value.
- 3
Raise GH gradually if low
If GH is below 6 (Neocaridina) or 4 (Caridina), begin raising it. Add remineralizer to your water change water to bring GH up by 1-2 points per day maximum.
Never raise GH by more than 2 points per day - sudden increases cause their own problems
- 4
Add emergency mineral source
Place a Wondershell, cuttlebone, or crushed coral in the tank. These slowly release calcium and can help while you stabilize GH through water changes.
- 5
Feed calcium-rich foods
Offer blanched spinach, kale, or specific shrimp calcium supplements. Shrimp can absorb minerals from food as well as water.
Recommended Products
These are informational recommendations only. Not affiliated with any brands.
Option 2: Long-term Prevention Protocol
- 1
Establish consistent remineralization routine
If using RO water, always remineralize to your target GH before adding to tank. Use the same remineralizer and ratio every time.
- 2
Test GH weekly
Add GH testing to your weekly routine. Log values to spot any declining trends before they cause problems.
- 3
Keep permanent mineral source in tank
A small piece of cuttlebone or Wondershell provides supplemental minerals between water changes.
- 4
Provide varied diet with calcium
Include calcium-rich foods regularly: blanched vegetables (spinach, kale, zucchini), commercial shrimp foods with calcium, and occasional mineral supplements.
Prevention Tips
Follow these practices to help prevent this problem from occurring in the future.
- Maintain stable GH at species-appropriate levels: 6-8 for Neocaridina, 4-6 for Caridina
- Always remineralize RO/DI water before adding to tank - never use pure RO water
- Test GH weekly and log results to catch declining trends early
- Keep a Wondershell or cuttlebone in the tank as supplemental mineral source
- Avoid large water changes that can swing GH dramatically
- Feed calcium-rich foods like blanched spinach and commercial mineral supplements
- Match new water parameters to tank water before adding - especially GH and TDS
- Use a quality remineralizer like Salty Shrimp GH+ that provides proper calcium:magnesium ratio
Track These Parameters with ShrimpKeeper
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Download FreeThe 'White Ring of Death' is one of the most heartbreaking problems in shrimp keeping because it is always fatal for the affected shrimp but completely preventable with proper care. To understand why it happens, you need to understand how shrimp molt. Shrimp grow by shedding their exoskeleton (molt) and forming a new, larger one. This process requires significant amounts of calcium and magnesium from the water. When a shrimp is ready to molt, the old shell splits between the carapace (head section) and the first abdominal segment (where the 'saddle' is on females). In healthy conditions with adequate minerals, the old shell splits cleanly and the shrimp wriggles out, then quickly hardens their new shell. However, when mineral levels are too low, two problems occur: the new shell forming underneath is too weak, AND the old shell becomes brittle and may crack in the wrong place or incompletely. The white ring appears when the old shell begins to separate but the shrimp cannot complete the molt. The white color is actually the exposed inner tissue becoming visible through the gap. Once this happens, the shrimp is essentially stuck in a broken shell with exposed tissue - they cannot go forward or backward and will die from the injury and stress. This is why the white ring is always fatal once visible - the damage is already done. But it's also why prevention is so effective - if you maintain proper GH, your shrimp will have the minerals they need and molts will proceed normally. Note that white ring is different from the normal white 'split line' that appears during a healthy molt. A healthy molt split happens quickly and the shrimp emerges within minutes. White ring of death shows a persistent gap that doesn't progress to a successful molt.
Frequently Asked Questions
Unfortunately, no. Once the white ring is visible, the molt has already failed and the shell has cracked improperly. The exposed tissue will lead to death within hours to days. There is nothing you can do for that individual shrimp. Focus instead on fixing your water parameters to prevent it from happening to other shrimp in your colony.
White ring is caused by insufficient minerals (calcium and magnesium) in the water, measured as GH (General Hardness). When GH is too low, shrimp cannot properly form their new shell or cleanly shed their old shell during molting. The result is a failed molt where the shell cracks but the shrimp cannot escape, showing as a visible white band around the body.
For Neocaridina (Cherry Shrimp, etc.): GH 6-12, with 7-8 being optimal. For Caridina (Crystal Red, Taiwan Bee, etc.): GH 4-6. If you're using RO water, you must add a remineralizer like Salty Shrimp GH+ to achieve these levels. Pure RO water has GH of 0 and will cause white ring.
No. During a normal, healthy molt, you may briefly see a split line as the shrimp emerges from its old shell, but this process completes within minutes and the shrimp emerges successfully. White ring of death is a persistent gap that doesn't progress - the shrimp is stuck and cannot complete the molt. If the white line has been visible for more than 30 minutes, it's white ring of death.
Individual shrimp may be more susceptible due to: being ready to molt when GH dropped, having higher mineral demands (berried females), being older/larger and needing more minerals, or having slightly different genetics. If one shrimp got white ring, your GH is marginal and others are at risk. Test and increase GH immediately.
You can, but it's not strictly necessary. Some keepers prefer to remove them to prevent the eventual decomposition from affecting water quality. Others leave them to let the shrimp pass naturally and allow tank mates to consume the body (which recycles the minerals). Either approach is fine - just remove the body within a few hours of death.
Cuttlebone and Wondershells help supplement minerals but dissolve slowly and may not raise GH quickly enough on their own. They're best used as a supplement alongside proper remineralization of water changes. If your GH is very low, you need to actively raise it through water changes with remineralized water, not just add cuttlebone.
Track Your Parameters with ShrimpKeeper
Most shrimp problems stem from parameter issues. Track your water quality, get alerts when things drift, and prevent problems before they happen.