The aquarium reading room

The why behind
the numbers.

The calculators tell you how much. These guides help you understand why, what a reading means, and what to do next.

Find your next read

12 practical guides Freshwater, planted & reef

A good place to begin
NH₃NO₂⁻NO₃⁻ AMMONIANITRITENITRATE AN ECOSYSTEM AT WORK

The nitrogen cycle explained

Ammonia → nitrite → nitrate, why it takes weeks, and how to know when it is done.

Read the guide

01 / Freshwater

Freshwater: A little understanding. A healthier tank.

From the first cycle to the weekly routine, get to know what is happening in your water.

CO₂ pH+ KH
Roots, leaves, and everything between.

02 / Planted

Planted: Make sense of what your plants need.

Understand the thinking behind fertilizer dosing before you reach for the bottle.

03 / Reef & saltwater

Reef & saltwater: Small parameters. A bigger picture.

Get familiar with the numbers behind a reef, from source water to coral chemistry.

ALKALINITY CALCIUM MAGNESIUM SALINITY

04 / Setup & hardware

Setup & hardware: Start on solid ground.

Think through the weight and placement before your aquarium becomes part of the room.

A closer look at your aquarium An illustrative aquarium cutaway showing the waterline, substrate, and tank dimensions. LENGTH HEIGHT THE WATERLINE ROOM FOR THE DETAILS
An empty tank is only the beginning.

05 / Troubleshooting

Troubleshooting: Something looking off?

Start with what you can see. Identify the problem, then work out what to change.

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