Frequently asked questions

Five US gallons rated, which holds about 4.3 gallons of water once substrate and the fill line are accounted for. Ten is better. The reason is buffer rather than swimming room: ammonia concentration, temperature stability and your margin for error all scale directly with water volume. The full argument, by volume.

It can survive in one, which is not the same thing. Bettas breathe atmospheric air through a labyrinth organ, so a bowl does not suffocate them - that true fact is the whole basis of the myth, and it answers a question nobody was asking. What kills a bowl-kept betta is ammonia with no filtration to process it, and cold with no room for a heater, over months. What actually happens in a bowl.

Long, and it is not close. A betta patrols horizontally and has to reach the surface to breathe, so a tall narrow column gives it a long climb and a short patrol. Given two tanks of the same volume, take the longer footprint. The tanks we would buy.

A 25W. The arithmetic asks for 15.1W in a room that drops to 68°F overnight, and nothing is sold at 15.1W, so you round up to the next size that exists. For a 3-gallon it is 10W; for a 10-gallon, 50W. The full table and the derivation.

Yes, in essentially every heated home in the United States. Bettas prefer around 80°F and American rooms commonly sit at 67-69°F. That gap does not close on its own, and a chronically cold betta is lethargic, eats less and has suppressed immune function - so what you usually notice is an infection weeks later that never gets blamed on temperature. The one case where you can skip it.

Between 76 and 82°F, held steady. We size heaters to 78°F rather than to the top of the range so the heater keeps some margin instead of running at its limit. Stability matters more than the exact figure - a tank steady at 76 beats one swinging between 74 and 82 every day. What happens at each end of the range.

Fluval’s own published P Series ratings. Each heater is rated to a tank capacity, and Fluval separately publishes that a lift of more than 12°F over room temperature needs additional heating capacity - which makes every rating a wattage, a volume and a maximum delta together. Dividing those out gives 0.278 to 0.347 watts per gallon per degree, and we use the largest of them, because undersizing a heater is the failure that kills fish. The whole derivation.

Yes, and not for the reason most people assume. A filter’s job is not clear-looking water - it is to host the bacteria that convert ammonia into something survivable. A tank can look pristine and be poisoning its occupant. Where the bacteria actually live.

Divide the published flow rate by your actual water volume. Over 6 turnovers an hour is too much for a long-finned fish that cannot swim out of the current. 4.3 gal of actual water x 4 turnovers an hour is about 17.2 GPH. Past roughly 25.8 GPH you are baffling the outflow or buying a different filter. Most nano filters publish no flow figure at all, so more often you read the fish: a betta that never leaves the far corner, or whose fins stream while it is stationary, is telling you. The ten-minute fix.

Under about ten gallons, a sponge filter driven by an air pump. It has no impeller, so it physically cannot injure a fin or a shrimp; its flow is set by a valve rather than reduced from an over-specified pump; and it survives a power cut with its bacteria intact. What it costs you is a black sponge in the display and an air pump humming on your desk. The full ranking.

Three to six weeks fishless, faster with seeded media from an established tank. No product removes the wait - bottled bacteria shortens it, and Seachem publishes a seven-day dosing schedule rather than a one-day one, which tells you how they see it. The tank is cycled when a 2 ppm ammonia dose processes to zero ammonia and zero nitrite within 24 hours. The full procedure.

25 to 50% weekly in a cycled, filtered tank - about fifteen minutes. Temperature-matched and dechlorinated: Seachem publishes 5 mL of Prime per 50 US gallons, so a 50% change on a rated 5-gallon needs about 0.22 mL. Use a syringe, not the cap. The schedule, and the routines that quietly make things worse.

Two or three granules once a day, with one or two fasting days a week. A betta’s stomach is roughly the size of its eye, which is far less than any portion that looks reasonable. Overfeeding causes an ammonia load, constipation in the fish, and a pest snail explosion, all at once. What to feed, and why.

Three to five years from hatching is the figure generally published - but shop fish are typically six to twelve months old when you buy them, so two to four years in your tank is the realistic expectation. A betta dying at eighteen months has not lived a normal life; it has had a shortened one. The four things that cost it years.

Invertebrates only - one nerite snail, or two or three Amano shrimp, with dense cover. No fish, of any species, in any number. Every fish small enough for the volume is a shoaling species that needs six of its own kind, which is a welfare problem regardless of how the betta behaves. The complete answer for this tank size.

There is no evidence they do. A betta is solitary and territorial - it does not shoal and does not pair-bond. Tank mates are something you want, which is a perfectly good reason to want them, but the decision should be made honestly because the animals carry the risk. The volume threshold, stated before the species list.

A nerite snail is the safest addition a betta tank can have - armoured, slow, and generally ignored. Amano shrimp work more often than they fail, provided there is real cover; cherry shrimp breed and become a food supply, which is a decision to make before buying rather than after. Shrimp and snails, in full.

Not male guppies. Long fins, bright color and a slow swim are exactly the three things that read to a betta as a rival betta - it is not a temperament question, it is what the fish looks like. Female guppies are possible at ten gallons and up, with the caveat that they arrive pregnant. The full comparison.

Anubias and java fern, tied to wood. Both are rhizome plants that attach to hardscape rather than rooting, so they work with any substrate or none, and Aquarium Co-Op publishes both as low light with no CO2 requirement. Never bury the rhizome - that is the most common way people kill them. The plants roundup.

Eight hours a day, on a timer. Longer grows algae rather than plants. If you have algae and otherwise healthy plants, cut to six hours for a fortnight before changing anything else - a controlled photoperiod is the best algae control there is and it costs nothing to run. Light requirements, and the units problem.

No, and every page says so. There is no test bench, no lab, and we do not own most of what is on this site. A testing claim is the easiest thing on a review site to fabricate and the hardest for a reader to verify, so we do not make one. What we do instead is read manufacturer documentation, link to every page a figure came from, record what each maker declines to publish, and show the arithmetic. The full method, including its limits.

Because we hold no verified live price for those products today. Prices render only from a live data layer with the retrieval date shown, and anything older than 48 hours disappears automatically. A stale price is worse than no price, because it looks like information. How this site is funded.

Because we only list products whose specifications we can trace to a published document - 20 of them at present. A short list we can defend beats a long one padded with marketing copy, and in this category the gaps are real: no nano filter publishes a flow rate and no nano light publishes PAR. Why that matters.

No. Diagnosis from a description is unreliable, most aquarium medications carry no dosing data for a four-gallon volume, and we hold no qualification that would make the attempt responsible. Where a symptom has a clear environmental cause - and with bettas it very often does - we say so, because fixing the temperature or the ammonia is not treatment, it is removing the cause. Where we draw that line.

No. We link to equipment only, and we would not link to livestock even if a marketplace made it easy - a live animal shipped to a stranger on the strength of an affiliate link is not a commission we want. Buy fish and shrimp from a shop where you can look at them first. The full disclosure.

Tell us - that is the most useful message you can send. Point at the page and the figure, and we will check the source and fix it with a dated note rather than editing silently. info@glassandgravel.com, or the contact form.