Can you put a betta fish with other fish in a Top Fin tank?

In a 5-gallon tank, a betta should be kept alone or with small invertebrates like nerite snails or cherry shrimp. In a 10-gallon or larger tank, compatible tank mates include: corydoras catfish (4–6 dwarf species), ember tetras (5–6), endler's livebearers (females only, 3–4), and mystery snails. Never keep two male bettas together — they will fight. Avoid fin-nipping species like tiger barbs and large or colorful fish that bettas may see as rivals.

Top Fin Essentials 5-Gallon Betta Starter Kit

Q: What is the best Top Fin tank for a betta fish?

The best Top Fin betta tank is the Essentials 5-Gallon Starter Kit. It includes a betta-safe adjustable low-flow filter, a pre-set 78°F heater, and an LED hood — everything a betta needs in one box. The 5-gallon size gives a male betta enough horizontal territory to be active and healthy. The 3-gallon All-In-One kit is a viable second choice for very limited spaces, but 5 gallons is the minimum recommended size for a betta to truly thrive.

Q: What size tank do betta fish need?

Betta fish need a minimum of 5 gallons. A 5-gallon tank gives a betta enough horizontal swimming space to establish territory, display natural behaviors like bubble nesting, and remain active. Tanks under 3 gallons cause stress, immune suppression, and shortened lifespan. The Top Fin 5-gallon Essentials kit is the most popular and recommended choice for a first betta setup.

Q: What temperature should a betta fish tank be?

A betta tank should be kept at 78–80°F (25.5–26.7°C). This is the optimal temperature range for betta splendens. At 78°F bettas are active, display vibrant color, and build bubble nests. Below 74°F bettas become lethargic and vulnerable to disease. Above 84°F their metabolism is overloaded. The Top Fin CH50 heater pre-sets to 78°F and is ideal for 5-gallon betta tanks.

Q: Is the Top Fin BettaFlo filter good?

Yes — the Top Fin BettaFlo is the gentlest filter in the Top Fin range and is specifically designed for betta fish. As an internal filter with an adjustable spray bar, it delivers water horizontally across the surface with virtually no directed current — ideal for bettas who are stressed by strong flow. It is the best Top Fin filter for dedicated 3–5 gallon betta tanks.

Q: How do I set up a Top Fin dual betta tank?

The Top Fin dual betta tank uses a solid center divider to keep two male bettas in separate water compartments. Set up each side independently: add substrate, a hide, and a plant on both sides. Ensure the divider is fully sealed from top to bottom — bettas can jump over or fit through small gaps. Run the heater in the center near the divider so both sides receive equal warmth. Each side needs its own feeding spot and hiding place so bettas cannot see each other constantly.

Q: Why is my betta fish not eating?

The most common reasons a betta stops eating: (1) Water temperature too low — check it is at least 76°F. Bettas stop eating below 72°F. (2) New tank stress — bettas often refuse food for 2–3 days after being moved. (3) Overfeeding — if pellets are decaying on the substrate, fast the betta for 1–2 days. (4) Illness — check for visible symptoms like clamped fins, spots, or bloating. (5) Food variety — try freeze-dried bloodworms or daphnia if the betta is bored with pellets.

Q: How often should I change the water in a betta tank?

In a filtered 5-gallon betta tank: change 20–25% of the water weekly (approximately 1–1.25 gallons). Use a gravel vacuum to remove waste from the substrate during each change. Always treat new water with a dechlorinator before adding it. In an unfiltered bowl or cup, 100% water changes are needed every 2–3 days — another strong reason to use a proper filtered tank.

TopFin Tanks® — Top Pick

Top Fin Essentials 5-Gallon Betta Starter Kit

★★★★½

The best all-in-one betta tank available at this price. Includes a genuinely betta-safe adjustable filter, a 78°F pre-set heater, and an LED hood — everything needed to give a betta fish a proper home in one box. The 5-gallon glass tank is sized correctly for one male betta to be active, healthy, and display his best colours.

Tank size: 5 US gallons

Filter: BettaFlo / SS10 adjustable

Heater: CH50 pre-set 78°F

Lighting: LED hood (dual mode)

Best for: 1 male betta

✓ Recommended

A betta fish kept in a bowl is surviving. A betta fish in a proper Top Fin betta tank — filtered, heated, planted, correctly sized — is thriving. The difference is visible within 48 hours: brighter colour, more active swimming, fins fully extended, and the appearance of bubble nests at the water surface that signal a genuinely content fish.

This page covers every Top Fin betta tank option with exact specifications, which filter and heater settings keep bettas healthy, a complete tank mate compatibility table, a live plant guide, a betta health section, and a full feeding guide — everything you need to set up the perfect Top Fin betta aquarium from day one.

In this guide

→ All Top Fin betta tanks compared → Why bettas need 5 gallons → Filter settings for bettas → Heater settings for bettas → Step-by-step setup guide → Dual betta tank guide → Tank mate compatibility → Water parameters → Live plants for betta tanks → Feeding guide → Betta behaviour guide → Common betta health problems → FAQ

All Top Fin Betta Tanks — Full Comparison

Top Fin offers five tanks well-suited to betta fish, ranging from 3-gallon desktop kits to 5-gallon full starter sets. Here is every specification you need to choose the right one.

Tank	Size	Filter	Heater	LED	Best for
Essentials 5-Gal Starter Kit ⭐ Top pick	5 gal	Adjustable HOB	✓ Included	✓ Dual mode	Single male betta — best overall
All-In-One Betta Kit — 3 Gal	3 gal	Internal BettaFlo	Optional add-on	✓ Included	Space-limited setups — buy heater separately
Split Bowfront — 5 Gal	5 gal	Integrated low-flow	✓ Included	✓ LED hood	Two bettas (divider included)
Half Moon Aquarium — 3.5 Gal	3.5 gal	Internal	✗ Not included	✓ LED hood	Desktop betta — add CH50 heater
Essentials 10-Gal Kit	10 gal	SilentStream 10	✓ Included	✓ LED	Betta + tank mates — reduce filter flow

All kits are freshwater only. The 3-gallon kits are viable but 5 gallons is the recommended minimum for a betta to display natural behaviour and build bubble nests consistently.

Why Betta Fish Need at Least 5 Gallons

The single most important decision in betta fishkeeping is tank size — and most beginners start too small. Here is exactly why 5 gallons is the minimum, and what happens in smaller tanks.

Bowl / <1 gal

Temperature swings hourly. No filtration. Ammonia spikes immediately. Betta lives weeks to months. Fins clamp, colour fades, stress lines appear.

2–3 gallon

Marginally better. Parameters still fluctuate quickly. Limited swim space. Insufficient territory for natural behaviour. Bubble nesting is rare. Life expectancy reduced.

5 gallon ✓

Stable parameters. Sufficient horizontal territory. Active swimming. Regular bubble nesting. Vibrant colour. 3–5 year lifespan with proper care. Can support cherry shrimp or snails.

The critical factor is horizontal space, not volume alone. Bettas are surface-breathing labyrinth fish that swim horizontally across their territory — they need tank length more than tank height. The Top Fin 5-gallon kit's 16-inch footprint gives a betta a meaningful territory to patrol, which directly reduces stress and increases the likelihood of bubble nesting behaviour.

Top Fin Betta Filter — Settings & Setup

Filter flow is the most critical equipment setting for a betta tank. Bettas are native to slow-moving water in Southeast Asia and cannot tolerate strong aquarium currents — a betta struggling against a filter stream is a stressed betta with a shortened lifespan.

Option 1 — Top Fin BettaFlo (recommended for 3–5 gal)

The BettaFlo is an internal filter that sits submerged inside the tank and delivers filtered water through a spray bar horizontally along the surface. This is the gentlest filter in the Top Fin range — the spray bar disperses flow into a wide, soft ripple rather than a directed stream. Flow is adjustable from near-zero to approximately 45 GPH. For a dedicated betta tank under 5 gallons, the BettaFlo is the best Top Fin filter choice.

Option 2 — SilentStream 10 (for 5–10 gal betta tanks)

The SilentStream 10 included in the 5-gallon Essentials kit requires adjustment for betta use. Follow these steps exactly:

Set the flow lever to the lowest position. The lever is on the side of the filter body. Move it fully toward the closed position to reduce flow to its minimum.

Observe your betta for 24 hours. A healthy betta swims freely with fins fully open. Signs of too much flow: fins clamped tight, betta hiding in corners or behind décor, betta swimming at an angle against the current.

Add a baffle if lowest flow is still too strong. Cut a piece of aquarium sponge slightly larger than the filter outlet and place it over the opening. This breaks the stream into a soft diffuse flow. Alternatively, tape a small plastic bottle cut lengthways below the outlet so returning water hits the plastic and disperses across the surface.

Confirm success with bubble nesting. A male betta building a bubble nest at the water surface within 2–3 days confirms the flow is correct and the environment is comfortable.

The bubble nest test: Bubble nests — floating clusters of tiny air bubbles at the water surface — are the clearest sign that your betta is content. A betta that never builds bubble nests is either too cold, too stressed by current, or unhealthy. Use this as your quality check for the entire tank setup.

Top Fin Betta Heater — Exact Settings

Correct betta heater settings

Target temperature: 78–80°F (25.5–26.7°C)

Heater model: Top Fin CH50 (50W) for 5 gal

Placement: Side glass, angled 45°, near filter

Thermometer: Digital probe (not strip)

Min safe: 74°F — below this = immune risk

Max safe: 82°F — above this = metabolic stress

Temperature warning signs

Too cold (<74°F): Lethargic, pale, resting on substrate, refusing food, fins clamped

Too cold: Susceptible to ich, velvet, and fin rot — cold = weakened immune system

Too hot (>84°F): Gasping at surface, erratic darting, rapid gill movement

Correct (78–80°F): Active, vibrant colour, fins fully spread, bubble nesting

Critical: The adhesive strip thermometer included in Top Fin starter kits reads 2–4°F warmer than actual water temperature. A strip reading of 78°F may mean actual water is only 74–75°F — the danger zone for bettas. Replace it with a $5 digital probe thermometer immediately.

Top Fin Betta Tank Setup — Step by Step

Hands-on time: 25–30 minutes. Then 4–6 weeks of cycling before adding your betta.

Choose the right spotAway from direct sunlight (causes algae), heating vents, and air conditioning. The surface must support ~55 lbs when full. A desk, bookshelf, or aquarium stand all work. Ensure a power outlet is within reach.

Rinse everything — no soap, everRinse the tank, substrate, and all decorations under cold running water. Soap residue kills fish. Even new gravel must be rinsed until the water runs clear — it is dusty from manufacturing.

Add substrate and betta-friendly décorAdd 1–2 inches of fine sand or smooth gravel. Place a cave or hide (bettas feel more secure with a retreat). Add silk or live plants — avoid sharp plastic plants that can tear betta fins. Place a leaf hammock near the surface if desired — bettas love resting on them.

Install filter on lowest flow settingHang the SilentStream 10 on the rear glass. Set the flow lever to minimum before plugging in. Do not plug in yet — wait until the tank is filled and primed.

Install heater at 45° near filter outletClip the CH50 to the side glass, angled at 45 degrees. Position it near the filter outlet so heated water circulates evenly. Do not plug in — heaters must soak for 15 minutes before powering on.

Fill slowly with dechlorinated waterPlace a plate on the substrate to avoid disturbing your arrangement. Fill with tap water to 1 inch below the hood. Add the full dose of Top Fin Water Conditioner — this neutralises chlorine and chloramines instantly.

Add bacteria starter, prime filter, plug everything inPour the bacteria starter into the tank. Wait 15 minutes. Prime the filter by pouring tank water into the filter body. Plug in the filter, wait 5 minutes, then plug in the heater. Fit the LED hood last.

Cycle for 4–6 weeks before adding your bettaAdd a pinch of fish food every 2 days as an ammonia source. Test weekly with an API Master Test Kit. The cycle is complete when ammonia = 0 ppm, nitrite = 0 ppm, nitrate shows a slight rise. Only then add your betta.

Top Fin Dual Betta Tank — Divider Setup Guide

The Top Fin Split Bowfront 5-Gallon includes a removable solid divider that splits the tank into two independent water compartments, allowing two male bettas to coexist safely in the same unit. Here is how to set it up correctly.

Before you start — dual betta tank rules:

✓ The divider must be fully opaque — bettas that see each other constantly will display aggressively all day, causing chronic stress

✓ Each side must have its own hiding place so neither betta can see the other

✓ Each side gets its own feeding spot — feed simultaneously on both sides to reduce stress

✗ Never use a mesh or transparent divider — constant visual contact stresses bettas continuously

✗ Dual tanks are not suitable as a permanent solution for most bettas — a dedicated 5-gallon per fish is better for their wellbeing

Position the heater centrally near the divider so both water compartments receive equal warmth. A single heater placed at the divider midpoint works well in this tank size. Decorate each side independently — give each betta a hide, at least one plant, and a clear swimming lane. Monitor both bettas daily for stress signs (pale colour, clamped fins, reduced appetite) and be prepared to separate them into individual tanks if signs of chronic stress appear.

Betta Fish Tank Mates — Full Compatibility Table

A 5-gallon betta tank is best kept as a single-specimen setup or with small invertebrates only. A 10-gallon opens more options. Use this table to choose wisely.

Species	5 gal	10 gal+	Notes
Cherry shrimp	✓ 8–10	✓ 15+	Excellent cleaners. Add heavy planting — bettas may eat shrimp in sparse tanks.
Nerite snails	✓ 2–3	✓ 3–4	Safe with all bettas. Best algae cleaners. Cannot reproduce in freshwater.
Mystery snails	✓ 1–2	✓ 2–3	Usually safe but some bettas nip at antenna — monitor first few days.
Corydoras catfish (dwarf)	✗ Too small	✓ 4–6	Bottom-dwellers — rarely interact with bettas. Use pygmy or habrosus species for 10 gal.
Ember tetras	✗ Too crowded	✓ 5–6	Small, peaceful, fast. Usually ignored by bettas. Good 10-gallon companion.
Endler's livebearers (female)	✗ Too crowded	✓ 3–4 females	Females only — colourful males may trigger betta aggression. Active and peaceful.
African dwarf frogs	⚠ Monitor	✓ 1–2	Generally peaceful but bettas sometimes nip frog legs. Feed frogs separately.
Neon tetras	✗ Too small	⚠ Risky	Some bettas tolerate them; others hunt them. Unpredictable — use ember tetras instead.
Any other male betta	✗ Never	✗ Never	Two male bettas will fight to death. No exceptions.
Tiger barbs / fin nippers	✗ Never	✗ Never	Will shred betta fins within hours.
Goldfish	✗ Never	✗ Never	Wrong temperature, excessive waste. Completely incompatible.

Betta Fish Water Parameters

Test your betta tank weekly with an API Master Test Kit — it measures all five critical parameters in one test. Here are the exact targets for a healthy Top Fin betta tank.

Parameter	Ideal range	Danger zone	What to do if wrong
Temperature	78–80°F	<74°F or >84°F	Adjust heater dial. Verify with digital thermometer.
pH	6.5–7.5	<6.0 or >8.0	Use pH up/down products in small increments. Never change pH more than 0.5 in 24 hours.
Ammonia	0 ppm	Any reading above 0	30% water change immediately. Check filter, reduce feeding. Tank may not be fully cycled.
Nitrite	0 ppm	Any reading above 0	30% water change. Tank is mid-cycle. Do not add fish until 0 ppm.
Nitrate	0–20 ppm	>40 ppm	Regular 20–25% weekly water changes keep nitrate controlled. Live plants help absorb nitrate.
Water hardness (GH)	2–10 dGH	>15 dGH (very hard)	Bettas prefer softer water. If tap water is very hard, use RO water blended 50/50 with tap.

Best Live Plants for a Top Fin Betta Tank

Live plants are the single biggest upgrade you can make to a betta tank. They absorb ammonia and nitrate, produce oxygen, provide resting spots and natural hides, and create the dappled cover bettas evolved in. All plants below work with the included LED hood.

Plant	Light	CO₂	Betta benefit
Java fern	Low	No	Broad leaves = resting platform. Tie to driftwood — never bury rhizome.
Anubias nana	Low	No	Bettas love resting on flat leaves. Extremely hardy — almost indestructible.
Java moss	Low	No	Provides dense cover — bettas hide and explore in it. Also shelters shrimp.
Marimo moss ball	Low	No	Bettas play with and nudge moss balls. Absorbs nitrate. Zero maintenance.
Amazon sword (mini)	Low–Med	No	Creates mid-height cover. Use dwarf/micro variety — standard swords outgrow 5 gal.
Cryptocoryne wendtii	Low	No	Planted in substrate. Creates natural-looking jungle floor betta cover.
Floating plants (hornwort, frogbit)	Low–Med	No	Mimics natural betta habitat. Surface cover encourages bubble nesting. Absorbs ammonia rapidly.
Betta leaf hammock (artificial)	N/A	N/A	Suction-cup plastic leaf placed near surface. Bettas rest on it for hours. Hugely popular addition.

Betta Fish Feeding Guide

How much and how often

Daily: 2–3 small pellets, twice per day (morning and evening)

Portion rule: Feed what your betta eats in 2 minutes — remove any uneaten food immediately

Fast day: Skip feeding one day per week — this prevents constipation and reduces waste buildup

Overfeeding signs: Uneaten food on substrate, bloated abdomen, cloudy water

Best betta foods

Primary: High-quality betta pellets (Top Fin Betta Bits or Fluval Bug Bites Betta)

Treats: Freeze-dried bloodworms (1–2 worms, 2–3 times per week)

Treats: Freeze-dried daphnia — excellent for preventing constipation

Avoid: Generic tropical flakes — too large and nutritionally unsuitable for bettas

Betta Behaviour Guide — Normal vs Stressed

Healthy betta behaviours ✓

Actively swimming throughout the tank at all levels

Fins fully fanned and open

Vibrant, saturated colour — no pale patches or stress lines

Building bubble nests at the water surface

Flaring at his own reflection occasionally (normal display)

Approaching the front glass when you walk by (recognition)

Eating eagerly at feeding time

Stressed or sick betta signs ✗

Fins clamped tight against body

Pale colour or visible dark horizontal stress lines along body

Resting on the substrate or hiding constantly

Gasping at the surface or rapid gill movement

Refusing food for more than 2 days

Torn, ragged, or deteriorating fin edges (fin rot)

White spots on body or fins (ich), or gold dust appearance (velvet)

Common Betta Health Problems & Fixes

Condition	Symptoms	Cause	Treatment
Fin rot	Ragged, receding fin edges, sometimes with black tips	Bacterial infection from poor water quality	25% water change daily for 1 week. Add aquarium salt (1 tsp/gal). Severe cases: API Bettafix or Melafix.
Ich (white spot)	White salt-grain spots on fins and body, scratching on décor	Ichthyophthirius parasite — usually from stress or cold water	Raise temperature to 82°F for 2 weeks. Use API Super Ick Cure. Daily 25% water changes.
Velvet	Gold or rust-coloured dust on body, clamped fins, lethargy	Oodinium parasite — very contagious	Dim lights (parasite is photosensitive). Copper-based medication (Seachem CopperSafe). Act fast.
Bloat / dropsy	Pinecone-shaped scales (scales raised), swollen abdomen	Bacterial infection affecting kidneys — often fatal	Isolate immediately. Kanaplex or Maracyn Two. Prognosis poor if scales are pineconing.
Constipation	Swollen abdomen without raised scales, not eating	Overfeeding, poor diet (too many dry pellets)	Fast for 2–3 days. Feed a single pea (skin removed) to act as laxative. Add daphnia to routine diet.
Ammonia poisoning	Red or inflamed gills, gasping, lethargy, reddish body tinge	Uncycled tank, overstocking, dead fish/plant decomposing	30–50% water change immediately. Remove source of ammonia. Use Seachem Prime as temporary detoxifier.

Related guides on TopFin Tanks®

→ Top Fin 5 Gallon Tank — complete setup guide → Top Fin Filter — BettaFlo & SilentStream guide → Top Fin Heater — CH50 complete guide → How to cycle a new aquarium → How to set up a Top Fin aquarium → TopFin filter not working — troubleshooting

Frequently Asked Questions

What is the best Top Fin tank for a betta fish?

The Top Fin Essentials 5-Gallon Starter Kit. It includes an adjustable low-flow filter, a 78°F pre-set heater, and an LED hood — everything a betta needs. The 5-gallon glass tank gives a male betta enough territory to be active, healthy, and display his best colours. The 3-gallon All-In-One betta kit is a viable second option for very limited spaces.

What size tank do betta fish need?

A minimum of 5 gallons. In smaller tanks, water parameters fluctuate too rapidly, there is insufficient horizontal swim space for territory behaviour, and immune function is suppressed by chronic stress. Bettas in properly sized filtered and heated tanks live 3–5 years. Bettas in bowls typically live 6–18 months.

What temperature should a betta fish tank be?

78–80°F (25.5–26.7°C). Below 74°F bettas become lethargic and prone to disease. Above 84°F their metabolism is overloaded. The Top Fin CH50 pre-sets to 78°F and is ideal for 5-gallon betta tanks. Always verify with a digital probe — the included strip thermometer reads 2–4°F warmer than actual water temperature.

Can you put a betta fish with other fish?

In a 5-gallon tank: keep a betta alone or with nerite snails and cherry shrimp only. In a 10-gallon: compatible options include dwarf corydoras (4–6), ember tetras (5–6), and female endler's livebearers (3–4). Never keep two male bettas together. Avoid tiger barbs, goldfish, and any colourful fish that bettas may see as rivals.

Is the Top Fin BettaFlo filter good for bettas?

Yes — it is the gentlest filter in the Top Fin range and is specifically designed for bettas. The internal spray bar delivers water horizontally across the surface with almost no directed current, which is ideal for bettas who stress in strong flow. It is the best Top Fin filter for dedicated 3–5 gallon betta tanks.

How do I set up a Top Fin dual betta tank?

Use the Top Fin Split Bowfront 5-Gallon with its solid opaque divider. Set up each side with independent substrate, a hide, and plants. Position the heater centrally near the divider for even warmth on both sides. Ensure bettas cannot see each other — constant visual contact causes chronic stress. Feed both sides simultaneously to reduce competition behaviour.

Why is my betta fish not eating?

Check: (1) Temperature — below 74°F bettas stop eating. (2) New tank stress — normal for 2–3 days after a move. (3) Overfeeding — fast for 1–2 days, then offer a single bloodworm. (4) Illness — look for visible symptoms like spots, bloating, or clamped fins. (5) Food boredom — try freeze-dried bloodworms or daphnia if they are tired of pellets.

How often should I change the water in a betta tank?

In a filtered 5-gallon betta tank: change 20–25% weekly (about 1–1.25 gallons). Use a gravel vacuum during each change. Always dechlorinate new water before adding. In an unfiltered bowl: 100% changes every 2–3 days — which is stressful for the fish and extremely time-consuming, which is why a proper filtered tank is always better.