How much substrate do I need for a 29 gallon tank?

For a 76 x 30 cm footprint at a 3 inch average depth you need about 18 litres: roughly 18 kg of aqua soil or 27 kg of sand. At 2 inches it is 12 litres.

What size heater for a 29 gallon planted tank?

A 100 W heater. Once substrate and rock are in, a 29 gallon holds about 82 litres (21.7 gallons) of water, which works out to 4.6 W per gallon.

How much filter flow does a 29 gallon planted tank need?

Aim for 330-490 litres per hour, which turns the water over 4 to 6 times an hour. Planted tanks like steady, gentle flow rather than a jet.

What light do I need for a 29 gallon planted tank?

A full-spectrum bar that covers the 30 inch (76 cm) length. Because the tank is 18 inches tall, run it at full output or add a second bar if you want carpet plants.

29 gallon planted tank setup

A 20 long footprint with 6 extra inches of height. More water stability and fish options, but the light has further to travel.

Dimensions: 76x30x46 cm; 30 x 12 x 18 in outer
Water volume: 82 L; 106 L (28.1 gal) gross, less substrate and rock
Substrate, 3 in average: 18 L; 18 kg aqua soil or 27 kg sand
Heater: 100 W; 4.6 W per gallon
Filter flow: 330-490; litres per hour, 4-6x turnover
Light timer: 6-7 hours; without CO2

Lighting

A 76 cm tank needs a bar that covers the full length so the ends do not go dark. At 46 cm tall, run it at full output or add a second bar for carpet plants.

Fits this tank

Aurora Smart 78 — RGB App-Controlled LED

78 cm bar, fits 70 to 95 cm tanks; your tank is 76 cm long.

$80

Filtration

Target 330-490 L/h.

Right-sized filter

4-in-1 Internal Filter & Pump

Adjustable internal filter rated to about 100 L, with lift-out media.

$30

CO2

Optional. Low-light plants grow without it; add CO2 if you want a carpet or red stems.

CO2 option

DIY CO2 Generator Kit — 2 L Stainless

Refill-free citric acid kit; enough for a tank this size without a gas cylinder.

$66

Substrate by depth

Slope it: shallower at the front glass, deeper at the back. The average depth is what sets how much you buy.

2 in average

12 L

12 kg soil, 18 kg sand

3 in average

18 L

18 kg soil, 27 kg sand

4 in average

24 L

24 kg soil, 35 kg sand

Custom tank? Use the substrate calculator

What to plant

Suits: Community planted tank with background stems and an open swimming area.

Amazon sword as a centrepiece (feed it root tabs)
Cryptocoryne and Anubias in the lower third
Hygrophila polysperma and Bacopa along the back
Java moss on a log for fry cover

Fish and shrimp

A school of 12 to 15 rummy-nose or cardinal tetras, a group of 6 corydoras, and a pair of dwarf cichlids or a centrepiece gourami.

Mistakes that cost people this tank

1One weak light. 18 inches of water dims a small bar; use a bar rated for a 76 cm tank at full power or run two.
2Overfeeding a big school. Uneaten food is the fastest route to an algae outbreak in a newly planted 29.
3Undersized filter. Aim for about 4 to 6 times the tank volume per hour, which is more than most 20 gallon filters move.

Quick answers

How much substrate do I need for a 29 gallon tank?: For a 76 x 30 cm footprint at a 3 inch average depth you need about 18 litres: roughly 18 kg of aqua soil or 27 kg of sand. At 2 inches it is 12 litres.
What size heater for a 29 gallon planted tank?: A 100 W heater. Once substrate and rock are in, a 29 gallon holds about 82 litres (21.7 gallons) of water, which works out to 4.6 W per gallon.
How much filter flow does a 29 gallon planted tank need?: Aim for 330-490 litres per hour, which turns the water over 4 to 6 times an hour. Planted tanks like steady, gentle flow rather than a jet.
What light do I need for a 29 gallon planted tank?: A full-spectrum bar that covers the 30 inch (76 cm) length. Because the tank is 18 inches tall, run it at full output or add a second bar if you want carpet plants.