Troubleshooter

Why is my shrimp not molting?

Quick answerShrimp molt every 4-6 weeks naturally. Lack of molting indicates calcium deficiency, low TDS, parameter instability, or shrimp is too young/old. Add mineral stones + verify GH.

Possible causes (4)

1. Calcium deficiency

Shrimp need calcium for shell development. Add mineral stones (Salty Shrimp Mineral GH+) or Indian almond leaves.

2. TDS too low

Below 150 TDS, neocaridina struggle to molt. Target 200-300 TDS. Add Salty Shrimp GH+ remineralizer.

3. Parameter swings

TDS or GH drops abruptly during water changes can prevent molting. Match new water exactly.

4. Young or old

Shrimplets molt every 1-2 weeks; adults every 4-6 weeks. Old shrimp (12+ months) molt less.

What to do next

Test water first - many "behavior" issues are actually water-quality problems. Use the water parameter checker to score your test results, the disease symptom matcher if you observe physical signs, or the general diagnoser to narrow further. Browse the disease database if illness is suspected.

More troubleshooting

Browse all behavior troubleshooting articles.

Aquarium-keeping fundamentals

Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.

Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.

Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.

Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.

Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.

Frequently asked questions

How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.

What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.

How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.

Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.

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