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Fin & Filter

Freshwater, for the first time

The first tank that doesn’t kill fish

Most first fish die in the first month, and almost always for the same reason: the tank was never cycled. This site works the whole setup out in order — the size, the filter, the four weeks before any fish, and the stocking that follows — with the arithmetic printed so you can check it against the box in your hand.

A planted freshwater aquarium lit from above
Guides published
38
Products we claim to have tested
0
Sponsored placements
0
Prices shown from memory
0

Everyone in this category says they tested twenty filters. We have not tested any, and we say so. What we did instead: compiled the published specifications, computed the turnover and wattage each tank actually needs, and showed the working on how we pick. Where there is no live price, the button reads Check price rather than showing a remembered number.

What to buy

The pick that won each shortlist

Each of these won a specific comparison, for a specific reason, against a number you can re-run. Click through for the full working and the runners-up.

A home aquarium set up on a wooden stand

Best Starter Kit

Aqueon LED Aquarium Starter Kit, 10 Gallon

A genuinely complete-ish 10 gallon kit, but the heater is preset and there is no test kit.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

A small planted aquarium on a desk

Best 10-Gallon Kit

Aqueon LED Aquarium Starter Kit, 10 Gallon

Bundled filter clears the turnover arithmetic; the preset heater is the compromise.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

A thermometer showing a water temperature reading

Best Heater

Eheim Jager TruTemp Heater, 50W

Recalibratable, tightly controlled, and rated by the maker for 7 to 16 gallons.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

A hang-on-back power filter running on a home aquarium

Best Overall Filter

Fluval AquaClear 20 Power Filter

Clears the 85 GPH a 10 gallon community tank needs, and its media is reusable rather than a cartridge.

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No live price is available for this product, so no figure is shown.

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A small aquarium filter fitted to the back of a ten gallon tank

Best for 10 Gallons

Fluval AquaClear 20 Power Filter

Clears 85 GPH with room to spare and has no cartridge to buy, ever.

Check price

#ad How we’re funded

No live price is available for this product, so no figure is shown.

Read why it won

A twenty gallon aquarium with a hang-on-back filter running

Best for 20 Gallons

Fluval AquaClear 30 Power Filter

The strongest single filter here at 150 GPH, and still about 12% under our 6x figure.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

A betta fish swimming in a planted aquarium

Best for a Betta

Various Air-driven nano sponge filter

The standard answer, and it is standard for a good reason: biological filtration with essentially no current.

Check price

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No live price is available for this product, so no figure is shown.

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An aquarium liquid test kit with reagent bottles and glass test tubes

Best Test Kit

API Freshwater Master Test Kit

Reads ammonia, nitrite and nitrate in fine increments, with over 800 tests in the box.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

Bottles of aquarium bacteria supplement beside a tank

Best Bacteria Starter

Tetra SafeStart Plus

Names its bacterial genera and asks for a single dose, which is the simplest protocol here.

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No live price is available for this product, so no figure is shown.

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Small community fish swimming in a planted aquarium

Best First Fish

API Freshwater Master Test Kit

The most important purchase on a stocking page, because hardiness is downstream of water quality.

Check price

#ad How we’re funded

No live price is available for this product, so no figure is shown.

Read why it won

Live aquarium plants growing in a beginner freshwater tank

Best Beginner Plant

Various Beginner live plants (java fern, anubias, hornwort)

Java fern, anubias and hornwort survive conditions that kill most aquarium plants.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

Bottles of aquarium water conditioner beside a tank

Best Water Conditioner

Seachem Prime

Removes chlorine and chloramine, and Seachem states it also detoxifies ammonia, nitrite and nitrate.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

A gravel vacuum siphon cleaning aquarium substrate

Best Gravel Vacuum

Various Bucket-and-siphon gravel vacuum

Cheapest way to do a proper gravel-vac water change, and perfectly adequate at this size.

Check price

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No live price is available for this product, so no figure is shown.

Read why it won

The five steps, in order

The whole job, start to fish

These are not product categories. They are the five decisions that determine whether the fish live, in the order you hit them.

An empty glass aquarium standing on a table before it is set up

Step one

Tanks, Kits & Gear

The first decision is a size decision, and it is the one most often got wrong. Bigger water is more stable water, and stability is what keeps a beginner's fish alive.

All 8 guides

Fine bubbles rising through aquarium water beside a filter outflow

Step two

Filters & Filtration

A filter's rated flow is measured with empty media and no lift. Loaded and running, real throughput is commonly a quarter to a third lower. Almost nobody corrects for it. We do, on every pick.

All 9 guides

Glass test tubes of clear liquid held up to the light

Step three

Cycling & Water Testing

Adding fish to an uncycled tank is the single most common way a beginner kills them. It is also completely avoidable, and it costs nothing but time and one test kit.

All 6 guides

Small tropical freshwater fish swimming among plants

Step four

Stocking & Fish Choice

The one-inch-per-gallon rule is the first thing a beginner is told and it is wrong. Adult size, body mass and schooling needs decide the answer, not purchase-day length.

All 7 guides

Hands rinsing equipment in a bucket of water

Step five

Water Care & Troubleshooting

Most aquarium emergencies are the same emergency wearing different clothes. Test first, water change second, product third — in that order, every time.

All 8 guides

Why trust a site that hasn’t tested anything

We compete on arithmetic, not on a lab we don’t have

The math is printed

Every filter and heater recommendation shows the figure it was judged against — the required turnover, the required wattage — so you can re-run it against any product we did not cover. The method is one page: how we pick.

Specs come from the manufacturer

Every number in a spec table is quoted from the maker’s own document or the retailer listing, and every page carries the links at the foot. Where a maker does not publish a figure, the page says so instead of estimating one.

Prices are live or absent

Prices render only from the live price layer and expire after 48 hours. When there is no live figure the button reads “Check price” — we never show a number we cannot stand behind today.

Every shortlist names a skip

A list where everything is recommended is a catalog, not advice. Our roundups say which product not to buy first and why, including products we would earn on.

No invented credentials

No expert panel, no test lab, no veterinary review board. One enthusiast reading manuals and doing math, and we would rather say that than borrow a credential. About the byline.

How we’re funded, in plain English

Amazon commissions on links you choose to use. It costs you nothing, it does not decide the rankings, and it is disclosed on every page that carries one. Read the disclosure.

If you read three pages

Read these first

A newly set up aquarium beside an open notebook

The whole first month

Start here: your first month, day by day

What to do in week one, what not to do, and the single step that decides whether the fish live.

Read the plan

Test tubes of aquarium water being compared against a color chart

The step everyone skips

How to cycle a fish tank

Four to six weeks of growing bacteria before any fish. This is the page that matters most on the site.

Read the method

A notebook, calculator and tape measure beside an aquarium filter

The method

How we pick, and the arithmetic behind it

Turnover, real-world throughput loss, heater wattage and lift. Every formula, with its sources.

See the working

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How this site is funded

Fin & Filter is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program. We earn a commission when you buy through a link on this site. It costs you nothing extra, no brand pays for a placement or a position, and the arithmetic that decides the rankings is published on how we pick so you can disagree with it specifically.

The full disclosure → · Editorial policy →