This tool provides a general estimate and does not replace professional veterinary advice.
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What is the Discus Stocking Level Calculator?
The Discus Stocking Level Calculator calculates how many discus can safely be stocked in a given tank size. 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.
A well-cared-for discus usually lives somewhere between 10 and 15 years. Diet-wise they are a carnivore, which shapes almost every feeding decision you make. Discus demand very warm, very clean soft water and near-daily water changes while growing. They are social and should be kept in groups of five or more. This is not a beginner species. The usual suspects for this species are hole-in-the-head disease, internal flagellates, bacterial infection from poor water, so any noticeable change is worth following up.
Discus quick facts
| Measure | Discus |
|---|---|
| Typical lifespan | 10–15 years |
| Diet | Carnivore |
| Mature at | About 1.5 years |
| Clutch size | 150–300 eggs |
How does the Discus Stocking Level Calculator work?
The recommendation is based on published care-guide minimums for discus, scaled to the animal's current or expected adult size. It is a starting point, not a verdict. Somebody who has actually examined your discus will always know more than a formula does.
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 Discus Stocking Level Calculator?
- Enter the tank volume in whichever unit you use (US gal, L, UK gal)
- Enter the adult body length in whichever unit you use (in, ft, cm)
- 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
Use this alongside your own observation, not instead of it. You notice changes in your discus that no calculator can pick up.
For related questions, see the other housing tools or browse every discus tool.
Before you rely on this
Two discus with identical numbers on paper can still need different care. Breed or line, body condition, activity level and any existing health conditions all pull the real answer away from the average. If your discus has a diagnosed condition, is pregnant, or is very young or very old, treat the figure here as the loosest of guides and let your vet set the actual target.
Sources and references
The formulas, reference ranges and species data behind the Discus Stocking Level 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.
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