Parameters Stable

FIVE GALLONS,
ZERO GUESSWORK

Nano aquariums under 80 liters, done right. Small tanks are not the easy option — they are the unforgiving one. We cover the cycle, the chemistry, and the gear so your first tank is not a casualty.

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Planted nano aquarium
pH
7.2 OK
TDS (ppm)
180 OK

Choose Your Path

Pick the journey that matches where you are — every path starts with water, not fish.

First Tank

Cycle first, fish later. The nitrogen cycle done honestly — no shortcuts, no week-one livestock, no surprises.

Start Path

Planted Path

Low-tech plants that actually survive, plus shrimp that earn their keep. No CO2 tank required.

Start Path

High-Tech Nano

Pressurized CO2, serious light, and aquascaping in a small footprint — where nano tanks stop being cheap.

Start Path

Three Real Nano Tanks

Ballpark street prices for reference — they shift with sales and region. None of these is "the best"; they solve different problems.

Tank Volume Approx. Price What It Solves Honest Caveat
Fluval Spec V 5 gal / 19 L ~$120 All-in-one with hidden filtration; the default first nano for a reason. Stock pump can be strong for a betta; expect to baffle it.
UNS 60U ~17 gal / 64 L ~$180 Rimless low-iron glass for aquascaping; you choose the gear. Tank only — filter, light, and lid all cost extra.
Waterbox Cube 20 20 gal / 76 L ~$299 Premium cube with sump-style back chamber; clean look, real volume. You are paying for fit and finish, not better water.

Prices for reference

Listed prices are typical street prices at time of writing, not promises. A bigger nano is almost always more stable than a smaller one — volume buys you forgiveness.

Build Tiers, Honestly Priced

What complete setups actually cost once you include filter, heater, light, and test kit.

Starter Nano — $100–$250

All-in-one tank, sponge or stock filter, heater, liquid test kit. Everything a cycled first tank needs, nothing it does not.

See Builds

Planted Sweet Spot — $250–$600

Rimless tank, proper plant light, aquasoil, easy plants. The best value-per-frustration tier in the hobby.

See Builds

High-Tech Showpiece — $600+

Pressurized CO2, high light, ferts on a schedule. Stunning results, weekly trimming, real running costs.

See Builds

Shrimp-Only Tanks

Neocaridina colonies thrive in 5–10 gallons where fish would struggle. Stable KH/GH matters more than gear here.

See Builds

Pico Bowls — Read First

Under 4 gallons, parameters swing fast and mistakes compound in hours. Plants and snails, yes. Fish, honestly, no.

Read the Warning

Office Tanks

Low-maintenance setups that survive weekends alone: tight lids, timers, hardy plants, modest stocking.

See Builds

Popular Guides

Essential reading before water touches glass.

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Tank Volume Calculator

Tank Size (Gallons)
0 20 Gal
Volume (Liters)
38
25% Water Change
9.5 L

Measure, Don't Guess

Small volumes leave no margin for estimating. Use our free calculators to nail actual water volume, convert EC to TDS, and plan water changes you can repeat every week.

  • Tank Volume Calculator
  • EC / TDS Converter
  • Water Change Planner
  • Stocking Sanity Check
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