Why are my cherry shrimp dying? What to check first

If several shrimp are distressed now

These are the checks I recommend doing first:

1. Check that the filter and air supply are running. Improve gentle surface movement if circulation has stopped or oxygen shortage is suspected.
2. Test ammonia and nitrite immediately, and check temperature. Record actual readings.
3. Remove confirmed dead shrimp and decomposing food.
4. If ammonia, nitrite or a likely contaminant is present, use a partial water change with properly conditioned, temperature-matched water of suitable chemistry. Re-test and repeat as the situation requires.
5. Pause feeding while investigating an acute water-quality problem, and seek experienced help if losses continue.

Stability does not mean leaving shrimp in polluted water. Equally, avoid replacing the entire aquarium or moving the colony into an uncycled container without a clear reason. If your replacement water may be the source of contamination, investigate that before adding more.

Build a timeline

To help narrow things down, I recommend writing down when losses started and what happened just beforehand: a water change, new plant, medication, filter cleaning, extra food, heatwave or power interruption. Note whether losses affect only newly bought shrimp or established animals too.

Test source water as well as the tank. Include pH, GH and KH, and compare with previous readings where available. A reading inside a broad care range does not rule out a rapid change from the conditions the shrimp were used to.

Common checks before considering disease

• Immature or disrupted filtration: a new tank, replaced filter media or a stopped filter can leave waste insufficiently processed.
• Temperature and circulation: check the thermometer and equipment rather than assuming the room feels comfortable.
• Overfeeding: hidden leftovers and dead material can worsen water quality.
• Recent additions: review treatments, plant preparation and possible household sprays or cleaning contamination.
• Water changes: check conditioner use and differences in temperature and mineral content.

Use product labels and manufacturer guidance to assess invertebrate safety. Do not assume that a fish medicine is safe for shrimp, or mix treatments because the first one has not produced an immediate improvement.

Is it a failed moult?

A transparent hollow shell is usually a normal moult. Shrimp often hide while their new shell hardens. A shrimp that has died partly trapped in its old shell may have suffered a moulting problem, but appearance alone does not reveal the underlying cause.

Review GH, the stability of the water and the diet. Adding calcium blindly can change conditions without solving the problem. Do not try to pull a live shrimp out of its shell.

When you need a closer identification

Unusual growths, persistent discolouration or repeated unexplained deaths need more careful investigation. Take clear photographs and provide the tank’s age, stocking, exact test readings and recent changes to an experienced shrimp specialist or aquatic veterinarian.

I can’t stress enough how important it is to identify a pest or disease before treating it. The checks in this guide can help you investigate, but they can’t diagnose the cause of a loss on their own. Keep suspected affected animals separate only when you can provide a suitable stable setup, and avoid transferring equipment between tanks without appropriate cleaning.

A single older shrimp can die in an otherwise healthy colony. Continue watching the group and recording findings rather than assuming either that every loss is harmless or that every loss is infectious.