This tool provides a general estimate and does not replace professional veterinary advice.
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What is the Catfish Water Change Calculator?
The Catfish Water Change Calculator works out how much water to change weekly for catfish tanks of a given size. Water quality is the single biggest factor in aquatic animal health. Far more animals are lost to poor water parameters than to disease introduced from outside.
A well-cared-for catfish usually lives somewhere between 5 and 15 years. As an omnivore, what a catfish needs from its diet changes across its life stages. Aquarium catfish range from 4cm corydoras to species over a meter, so confirm adult size before buying. Most are bottom-dwellers needing smooth substrate to protect their barbels and their own sinking food. Keep an eye out for barbel erosion from sharp gravel, starvation when assumed to be scavengers, ich. These are the conditions catfish are most commonly seen for.
Catfish quick facts
| Measure | Catfish |
|---|---|
| Typical lifespan | 5–15 years |
| Diet | Omnivore |
| Mature at | About 1.5 years |
| Clutch size | 200–400 eggs |
How does the Catfish Water Change Calculator work?
The figures are based on commonly cited aquarist rules of thumb and safe parameter ranges for catfish, scaled to your tank or livestock details. It is a starting point, not a verdict. Somebody who has actually examined your catfish will always know more than a formula does.
What affects the result
- Tank size and current stocking level
- Filtration capacity: which affects how much waste the system can safely process
- Feeding habits: since overfeeding is a leading cause of poor water quality
- Source water quality before treatment, which varies by location
How do you use the Catfish Water Change Calculator?
- Enter the tank volume in whichever unit you use (US gal, L, UK gal)
- Enter the current nitrate
- Enter the target nitrate
- Pick your stocking level (Lightly stocked, Moderately stocked, Heavily stocked)
- Press Calculate, then read the result alongside the sources listed below
Worth doing: jot down the date and the result each time. A single number tells you little, but a trend across a few months tells you a lot about your catfish.
For related questions, see the other water tools or browse every catfish tool.
Before you rely on this
Averages hide a lot of variation. The figure here reflects what is typical for catfish, but your catfish may sit well outside it for perfectly ordinary reasons. Use the result to spot changes over time in your own animal rather than to compare it against other people's pets.
Sources and references
The formulas, reference ranges and species data behind the Catfish Water Change Calculator come from these veterinary references, professional bodies and published research.
- University of Florida IFAS ExtensionAquacultureedis.ifas.ufl.edu(opens in a new tab)
- Merck Veterinary ManualReptilesmerckvetmanual.com(opens in a new tab)
- ARAVAssociation of Reptilian and Amphibian Veterinariansarav.org(opens in a new tab)
- Merck Veterinary ManualExotic and Laboratory Animalsmerckvetmanual.com(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.