January 29, 2023

How to custom plumb your Red Sea, Waterbox or Aqua One Tank

DIN plumbing and metric sizes refer to the standard measurement systems used for pipes, fittings, and valves in the plumbing industry. Plumbing can also be found in mass produced fish tanks from companies such as Aqua One and Red Sea.

DIN, or Deutsches Institut für Normung, is a German standard for plumbing and piping systems. DIN measurements are commonly used in Europe and other parts of the world, and are based on millimeter measurements. DIN measurements are commonly used to aquarium brands such as Red Sea, Waterbox and Aqua One aquarium systems.

Metric sizes, on the other hand, are based on the International System of Units (SI) and are used primarily in the United States, Canada, and other countries that have adopted the metric system or "DN" in Australia with brands such as Holmans commonly found in Bunnings. Metric measurements are also based on millimeter measurements.

One key difference between DIN and metric sizes is that DIN measurements are based on nominal sizes/Outer Diameter (OD), while metric sizes are based on actual sizes. This means that a DIN pipe or fitting may have a slightly different actual size than its nominal size, while a metric pipe or fitting will have the same actual size as its nominal size.

(diagram showing difference on advertised measurements)

Another difference is that DIN fittings have a standard thread pitch of 1.5mm, while metric fittings have a standard thread pitch of 1mm. This means that DIN fittings will have more threads per inch than metric fittings of the same size.

It's important to note that the plumbing industry in Australia primarily uses DN Metric standards and not DIN European sizes found on Red Sea, Waterbox and Aqua One systems.

When looking to build custom manifolds or replumbing to add things like roller mats, reactors and chilllers, you will need to purchase the correct plumbing measurent. See bellow an example of a custom built manifold on Waterbox Aquarium using Sanking Plumbing pieces, altered on the standard plumbing included with the set.

(example of a custom manifold on a modified Waterbox sump)

If your tank already uses Holman DN sized plumbing, you can use converters, found here. A converter union will have one side with DN to fit into DN pipes,with the other side DIN. Another option is to use a Push In Converter, which will require the use of couplings or elbows.