This tool provides a general estimate and does not replace professional veterinary advice.
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What is the Coral Tank Size Calculator?
The Coral Tank Size Calculator recommends minimum tank size in liters or gallons for keeping corals. Undersized housing is one of the most common and most fixable welfare problems in pet keeping, it affects everything from stress levels to exercise to litter/waste management.
Corals generally live 10-50 years when they are well looked after. As a filter feeder, what a coral needs from its diet changes across its life stages. Corals are colonial animals, not plants, and depend on stable salinity, alkalinity, calcium and strong lighting. They are the least forgiving part of a reef tank, where stability matters more than any single value. Keep an eye out for bleaching from heat or light stress, tissue recession from unstable alkalinity, brown jelly infection. These are the conditions corals are most commonly seen for.
Coral quick facts
| Measure | Coral |
|---|---|
| Typical lifespan | 10–50 years |
| Diet | Filter feeder |
| Mature at | About 3 years |
| Clutch size | 0–0 eggs |
How does the Coral Tank Size Calculator work?
The recommendation is based on published care-guide minimums for corals, scaled to the animal's current or expected adult size. Treat the result as a well-founded estimate. Every coral is an individual, and your vet's judgement outranks any online tool.
What affects the result
- Adult size: housing should be sized for the animal's full-grown dimensions, not its current size if still young
- Number of animals being housed together, since space needs don't simply divide evenly
- Activity level and natural behavior, such as climbing, digging or swimming space
- Whether the space is temporary (travel/carrier) or permanent (everyday housing)
How do you use the Coral Tank Size Calculator?
- Enter the adult body length in whichever unit you use (in, ft, cm)
- Answer "How many of this species?"
- Pick your filtration and planting (Standard filter, no live plants, Strong filter or heavily planted, Minimal filtration)
- Press Calculate, then read the result alongside the sources listed below
Bring the number to your next appointment. Vets can work with a figure and a date far more easily than with "he seems a bit off lately".
For related questions, see the other housing tools or browse every coral tool.
Before you rely on this
One number on one day is rarely the full picture. What matters more is the direction of travel: whether your coral is trending steadily, drifting, or changing suddenly. A sudden change is always worth a call to your vet, even when the individual figure still falls inside a normal range.
Sources and references
The formulas, reference ranges and species data behind the Coral Tank Size Calculator come from these veterinary references, professional bodies and published research.
- RSPCAAdvice and Welfarerspca.org.uk(opens in a new tab)
- Merck Veterinary ManualExotic and Laboratory Animalsmerckvetmanual.com(opens in a new tab)
- pdsa.org.ukPDSA Pet Health Hubpdsa.org.uk(opens in a new tab)
- University of Florida IFAS ExtensionAquacultureedis.ifas.ufl.edu(opens in a new tab)
- Merck Veterinary ManualRoutine Care and Breedingmerckvetmanual.com(opens in a new tab)
- Built on veterinary referencesFormulas and ranges come from veterinary manuals, university research and welfare bodies, listed above for you to check.
- Instant resultsNo page reload, no waiting and no account. Enter your details and the result appears straight away.
- Private by designCalculations run in your browser. Nothing you enter is stored on our servers or shared with anyone.
- Always freeEvery XpertsPet tool is free to use, with no premium tier and nothing to sign up for.