Poor match2 concerns

Cherry shrimp and Goldfish

Can these two share a tank? The assessment below is derived from stored behavioural and environmental traits, not from a compatibility chart.

VerdictPoor matchhigh confidence

Workable only in unusual circumstances. Not a pairing to plan around.

Minimum volume: 400 L
Minimum length: 150 cm
Factors considered: 6

Concerns

majorinvertebrate risk

Goldfish will take adult dwarf shrimp. Heavy planting reduces losses but does not prevent them; a shrimp colony will not establish.

Derived from: traits.predation.adultDwarfShrimp

moderatetemperature

The shared band 18–22 °C sits at the top of one animal's range, so that animal is permanently at its limit even though the overlap looks generous. The overlap sits at the extreme of at least one animal's range, so that animal is permanently at its limit. A non-empty overlap is not the same as a suitable one.

Derived from: environment.temperature range position on both records

Why it can work

pH requirements overlap at 7–8.
Hardness requirements overlap at 8–15 °dGH.
Cherry shrimp needs a group of at least 10. Kept in smaller numbers it is not simply lonely — shoaling species held below their threshold show chronic stress behaviour, colour loss and, in several species, increased aggression towards tankmates.
The two occupy different levels of the tank, which reduces direct competition for space.

Conditions

Most interesting pairings are conditional on something. These are the things the keeper can actually change.

At least 10 Cherry shrimp, counted as one group
At least 400 L with a footprint of 150 cm or more, before counting anything else in the tank

Derived, or documented?

These are different claims and are shown separately. The verdict above is derived from stored traits — arithmetic on AquariumHQ's own records. Whether the pairing is actually reported to work is a separate question, and for most pairs the honest answer is that we hold nothing.

Environmental compatibility

Derived from stored traits

Temperature, pH, hardness, size and behavioural traits compared between the two records. Sound as far as it goes, and it is not evidence that the pairing works.

Behavioural evidence

Widely reported in practice

Reported consistently across aquarium practice without a single citable source. Treated as real but not as measurement.

AquariumHQ's overall position

Temperature is the one thing that works. The colony is food as the goldfish grows, and the water quality a goldfish produces is the second problem behind the first.

Factor by factor

Goldfish eat what fitsReported
Goldfish are opportunistic omnivores that investigate everything by mouth. An adult cherry shrimp fits.
TemperatureDerived
Both tolerate the cooler end, which is the one respect in which the pairing is not a compromise.
BioloadDerived
Goldfish waste output is high relative to length, and dwarf shrimp are sensitive to the water quality that results.

What the answer depends on. A single cell in a compatibility chart cannot hold any of these.
Depends on	How much
Tank size and dimensions	minor
Life stage	significant
The individual animal	minor

How good is the overlap?

Whether two ranges intersect is a necessary condition, not evidence. What matters is WHERE the shared band sits: an overlap at the top of one animal's range and the bottom of the other's is a forced compromise however wide it looks, and it is the case a simple intersection test cannot see.

Each dimension assessed for the quality of the overlap, not merely its existence.
Dimension	Assessment	What that means here
Temperature	One animal at the edge of its range	The shared band 18–22 °C sits at the top of one animal's range, so that animal is permanently at its limit even though the overlap looks generous.
pH	Comfortable for both	The shared band 7–8 pH sits centrally in both ranges, with room to drift.
Hardness	Workable	The shared band 8–15 °dGH is usable, though it does not sit centrally for both animals.

Factor by factor

Every factor states what it rests on. Most are derived from the traits stored on both records — sound arithmetic on AquariumHQ's own data, and not a report about how the pairing actually goes. Where a factor says 'not known', the data is missing and saying so matters, because a missing factor and a favourable one look identical once both are absent.

2 evidence-backed17 derived0 not known

Factor	Basis	Finding
Temperature	Derived from stored traits	One animal at the edge of its range. The shared band 18–22 °C sits at the top of one animal's range, so that animal is permanently at its limit even though the overlap looks generous.
pH	Derived from stored traits	Comfortable for both. The shared band 7–8 pH sits centrally in both ranges, with room to drift.
Hardness	Derived from stored traits	Workable. The shared band 8–15 °dGH is usable, though it does not sit centrally for both animals.
Body size	Derived from stored traits	Goldfish reaches about 35 cm against 4 cm for Cherry shrimp — a ratio of 8.8. Size disparity drives opportunistic predation independently of temperament.
Predation	Derived from stored traits	Highest predation risk in either direction is "high".
Territoriality	Derived from stored traits	Neither animal holds a territory.
Breeding aggression	Derived from stored traits	Neither becomes notably more aggressive while spawning.
Fin-nipping	Derived from stored traits	No nipper-and-target combination between these two.
Aggression	Derived from stored traits	Strongest intraspecific aggression across the pair is "none". It bears on the pairing because a fish under pressure from its own kind redirects.
Social requirements	Derived from stored traits	Cherry shrimp needs at least 10. A shoaling species held below its threshold shows chronic stress and, in several species, increased aggression towards tankmates.
Group-size dependency	Derived from stored traits	The outcome depends on group size as much as on the pairing: under-grouped shoalers nip more and hide more.
Tank zone	Derived from stored traits	The two use different levels of the tank, which reduces direct competition for space.
Activity level	Derived from stored traits	Activity levels are compatible.
Food competition	Derived from stored traits	Different feeding strategies, so direct competition is limited.
Risk to shrimp and snails	Derived from stored traits	Highest risk either animal poses to dwarf shrimp or snails is "near-certain".
Effect on plants	Derived from stored traits	Goldfish eats plants, which constrains the aquascape rather than the pairing.
Tank dimensions	Derived from stored traits	The more demanding of the two needs at least 400 L and 150 cm of length before anything else is in the tank. Volume alone does not describe a home for a fish that swims in straight lines.
Life stage	Evidence-backed	Life-stage dependency: significant. See the documented record.
Individual variation	Evidence-backed	Individual variation: minor.

Environmental overlap

Parameter	Shared range	Reading
Temperature	18–22 °C	Aim for the middle of the shared band.
pH	7–8	Stability matters more than the exact figure.
Hardness	8–15 °dGH	Check your source water before committing.

What this assessment cannot tell you

Individual temperament varies, particularly in cichlids and in bettas, and can override a favourable verdict for Cherry shrimp or Goldfish.
The assessment is for the pair in isolation. A third species can change the outcome in either direction.
Both animals are assessed at adult size, not at the size they are sold.
A verdict is a statement about probability, not a guarantee.

The two species

Cherry shrimpNeocaridina davidiThe most forgiving dwarf shrimp in the hobby and the usual first one. Colour strains — red, yellow, blue, green, orange — are all the same species, which is why mixing them produces wild-type brown offspring within a few generations.GoldfishCarassius auratusA large, long-lived, cold-water pond fish that has spent a century being sold as a bowl ornament. Single-tail goldfish reach 25–30 cm, live for decades, produce an enormous waste load and cannot be kept properly in an indoor tank of ordinary size.