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What filter flow for a 29 gallon tank?

30 × 12 × 18 in · freshwater planning

116–174 GPH for a community

29 gallon · filter flow

29 gallon equipment and layout plan

A rectangular layout supports a straight front swimming lane and a rear equipment zone. The 30 × 12-inch base has an aspect ratio of 2.5:1. A lid or light must span roughly 30 inches; measure rim openings and bracket adjustment before ordering.

A HOB can keep hoses out of a small setup. Compare its loaded flow against the community target; a compact canister is an alternative when intake protection and maintenance access work.

Layout checkThis tank
Return-to-far-end distance30 in
Front-to-back path12 in
Community midpoint, 5×145 GPH
Messy-load midpoint, 9×261 GPH

An outlet directed down the 30-inch long axis can help reach the opposite end. Observe plants and fine debris for stagnant spots. Within 12 inches of width, separate the intake from the return enough to avoid an obvious short circuit.

Moving up from the 25 gallon changes GPH at the community midpoint from 125 to 145: an increase of 16%. Budget for the larger requirement rather than reusing the smaller plan unchanged.

First decisions for this small setup

Check the space behind the 30-inch back rim for a HOB body, lid cutout and power cable. Water must return without splashing onto the stand. A heavily baffled outlet may reduce useful circulation, so inspect the far corner after fitting the baffle.

The working

29 nominal gal × 4–6 turnovers/hour = 116–174 GPH. The messy-fish planning range is 29 × 8–10 = 232–290 GPH.

UseTurnover per hourTarget GPH
Community4–6×116–174
Messy fish8–10×232–290

Assumptions and limits

These circulation ranges are planning heuristics, not stocking limits. Advertised pump ratings often exclude media and lift; actual loaded flow can be lower. Some manufacturers publish both figures. Check which rating you are reading. Baffle strong outlets for gentle-water fish; biological media capacity matters too.

Turnover assumptions are shown explicitly. No single flow rate makes an unsuitable species fit.

Adjust measurements with the filter flow calculator

Questions before you buy

What dimensions does this 29 gallon calculation use?

It uses a rounded 30 × 12 × 18 inch rectangle. Actual dimensions vary by brand and frame; measure your own tank.

What is the filter flow estimate for a 29 gallon tank?

116–174 GPH for a community

Equipment to check

Compare aquarium filter media. Check dimensions, capacity and product instructions before buying.

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