Before You Order the Tank For a pair of Ocellaris Clownfish (Amphiprion ocellaris), 20 US gallons / about 76 liters is a commonly published minimum, but for a permanent display I would usually specify around 75–120 liters for a simple pair-only system and 120 liters…
Read MoreQuick Answer: Goldfish need a minimum of 20 gallons for one fancy goldfish, 30 gallons for two, and 55+ gallons for a common/comet goldfish. The "goldfish bowl" is a death sentence — goldfish grow to 6-12 inches, they're messy, and they produce 10x more waste…
Read MoreSummary: Arowana fish need a minimum of 180 gallons for a single juvenile, 250 gallons for an adult, and 400+ gallons for a pair. The tank must be at least 8 feet long because adult arowanas grow to 24-36 inches and need horizontal swimming space.
Read MoreThe Specification I Would Change Before Approving the Order For adult koi, a conventional home aquarium is usually the wrong permanent system. Koi are domesticated common carp (Cyprinus carpio), and FishBase records common carp reaching 120–129 cm at maximum size, with a maximum published weight…
Read MoreChoose the Fish List Before You Choose the Aquarium Freshwater and saltwater fish should not be selected by color or body size alone. The real differences are in adult size, social behavior, swimming pattern, water chemistry, territorial needs, feeding, biological load, and—in marine systems especially—compatibility…
Read MoreFreshwater and saltwater fish should not be selected by color or body size alone. The real differences are in adult size, social behavior, swimming pattern, water chemistry, territorial needs, feeding, biological load, and—in marine systems especially—compatibility with corals and other invertebrates. A 2.5 cm Neon…
Read MoreAbstract: I've killed 17 fish in 2 years. I know exactly which fish are "beginner-friendly" and which are beginner traps. The fish that die the most are the ones the pet store says are "perfect for beginners." Here's my honest list of what actually survives…
Read MoreQuick Answer: Cloudy aquarium water is not one problem — it's four. White cloudy water means a bacterial bloom (usually after a new tank setup). Green water means algae bloom (too much light + too many nutrients). Brown water means tannins (from driftwood or new…
Read MoreAbstract: A sump aquarium is not "set it and forget it." After timing myself on my own sump maintenance for 3 months, I spend 20 minutes per day on routine checks, 45 minutes per week on water changes and filter cleaning, and 2 hours per…
Read MoreThree Things I Test Before I Call a Sump Finished A well-designed sump aquarium should survive three ordinary events without drama: the return pump stops, several liters of water evaporate, and the drain runs continuously without turning the cabinet into a washing machine. Those three…
Read MoreWhat I Tell People Before They Reach for the Bucket If ammonia or nitrite is elevated and fish are already in the aquarium, a properly performed partial water change is one of the fastest ways to reduce immediate exposure—but it does not repair the reason…
Read MoreQuick Answer: Three numbers matter. Ammonia must be 0.00 mg/L. Nitrite must be 0.00 mg/L. Nitrate should be under 20 mg/L for freshwater, under 10 mg/L for saltwater. If any of these are off, your fish are stressed — even if they look fine. I've…
Read MoreBefore You Ask for a Tank Size, Count the Kilograms of Seafood For a restaurant saltwater holding tank, choose the tank and sump from the maximum live seafood biomass, species, holding temperature, feeding policy, and expected holding time—not from the length of the restaurant wall.
Read MoreSummary: For a bedroom marine tank, 40-60 gallons is the sweet spot. Bigger isn't better — you need to consider noise (return pump), heat (heaters and lights), and the view from your bed. After designing 30+ aquarium installations, I can tell you: the #1 mistake…
Read MoreWhat I Would Put in the Living Room For a permanent living-room marine aquarium with a sump, I would usually start around 300–500 liters (80–130 US gallons) for a first serious system, rather than pushing toward the smallest tank possible. A practical custom size is…
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