Planted aquarium setup
Most first planted-tank builds get one of three things wrong: the tank size, the light, or the substrate. All three are fixable at the buying stage and painful to fix once the tank is wet. This silo is the map to which gear fits your situation, in the order it actually matters.
When I set up my first planted tank in 2013, I put a tall 29-gallon next to a window with a stock incandescent hood. Within a month it was a hair-algae forest. The lesson sat there in plain view: footprint over height, no direct sun, real planted-tank LED. Almost every planted-tank rookie mistake is a buying mistake — which is what this section is for.
Below: a 60-second decision tree, our current featured guides, and the spec checklist worth running before you commit to a kit.
How to choose the right setup
Four questions. Answer them honestly and you'll know which guide to read next.
Low-tech or high-tech?
- Low-tech — No pressurised CO2. Easy plants, slower growth, lower running cost. The right answer for almost every first build.
- High-tech — Pressurised CO2 to about 30 ppm, brighter LED, weekly dosing. Supports the demanding carpets and reds. Adds about $250 to setup and a maintenance hour per week.
What size tank?
- 10 gallon — Tight, swings on parameters. Best as a single-betta or shrimp tank with plants.
- 20 gallon long — The beginner sweet spot. 30 × 12 × 12 in footprint, easy to light, room to aquascape.
- 29 gallon — More water, vertical room, slightly harder to light to the substrate.
- 55 gallon — Genuine aquascape territory, higher cost on lighting and CO2.
How much can you spend?
- Sub-$300 — Low-tech 10 or 20 gallon. All-in-one kit, plant the easy shortlist, skip CO2.
- $300–600 — Low-tech 29 or 55 gallon, or a high-tech 10–20 gallon. Better LED, real filter, plants you have actually picked.
- $600+ — High-tech 20 gallon or larger with pressurised CO2, premium light, and the plants that justify both.
Kit or piece-by-piece?
- Kit — Tank, hood, filter, and heater in one box. Faster, often cheaper, but the bundled light is rarely planted-tank-grade.
- Piece-by-piece — Slower, more research, but every component fits the plants you want to keep. The right answer once you know what you are after.
Most first builds should start with a kit, then upgrade the light within the first month if plants are struggling. The cost difference is usually $40 to $80, and the kit components stay useful as backups.
Featured guides
The current published guides in this silo. More land each batch.
Landing next: Low-tech vs high-tech planted tank, Complete 20-gallon planted-tank shopping list, and Best aquascaping tools (scissors, tweezers, pinsettes).
What matters in a planted aquarium setup
The spec checklist worth running on any kit or piece before you buy. Manufacturer copy sells the photo; this is what the photo leaves out.
Tank dimensions — long beats tall
A 20-gallon long aquascapes better, lights cheaper, and shows fish better than a 20-gallon tall. Footprint and depth decide what you can plant; volume mostly affects parameter stability. Pick by footprint first.
The light bundled with the kit
Stock kit lights are usually low-output white LEDs designed to show the fish, not grow plants. Most planted-tank keepers swap the bundled light within a month. Read the LED light for a planted tank guide for what to look for — the short version is dimmable, with planted-tank-targeted spectrum, and PAR that hits the band you want at substrate depth.
Filter capacity — manufacturer ratings inflate
A filter rated for a 50-gallon tank typically does 30 in real-world planted-tank conditions (slower flow from heavy media, plant baffles in the way). Aim for four to six times tank turnover per hour on low-tech, six to ten on high-tech. Canisters beat hang-on-back for tanks above 29 gallons.
Heater wattage — five watts per gallon
A 100-watt heater for a 20-gallon tank is the standard rule. Stick to known brands with an external controller or accurate dial — Tetra, Eheim Jager, Fluval, Cobalt. Cheap unbranded heaters are how tanks cook overnight or freeze in winter.
Substrate choice
Aquasoil or capped inert. Plain gravel "works" for the simplest plants but loses most of the planted-tank advantage. See the best aquarium soil comparison for the side-by-side.
Stand and floor
A 20-gallon planted tank weighs about 220 pounds full; a 55 closer to 625. Use a tank-rated stand with even support across the base. A wobble in the stand becomes a stress fracture in the seams.
What we don't recommend
Cheap globe or bowl tanks
They look the part. They light poorly, filter poorly, and the curved glass distorts the view. Skip — a basic rectangular 10-gallon is a better planted tank for less money.
Stock incandescent or single-strip white LED hoods
Anything that came bundled with the tank a decade ago, or a stock hood that ships with a single white-LED strip designed to "show the fish." Plants need either spectrum-targeted LED or a real planted-tank fixture. Run an old stock hood and you grow algae.
Heaters without a thermostat
"Always-on" heaters or non-thermostatic models pop up cheap. They are how tanks reach 90°F on a warm afternoon. Always buy a thermostatic heater.
"Planted-tank" kits without a real planted-tank light
Many kits labelled "planted" ship a white-light LED with no documented PAR or spectrum data. That is not a planted-tank light. The planted aquarium kit guide flags the ones that cheat and the ones that deliver.