Hydor Ario-4 Aquarium Aerator

Ario 4 is the largest and strongest of all Ario series water aerators made by the well known Italian aquatic pump and accessories manufacturer Hydor.

The Ario pump is equipped with a special impeller that breaks the air in tiny spray-like bubbles allowing it to stay longer into the water aiding diffusion. Something common in protein skimmers for marine aquariums.
It is designed to be installed either under the gravel or on the glass walls of the aquarium using the specialized base for the pump.
The pump intake is protected by a small sponge, and an acrylic disk protects the impeller from gravel bits entering its chamber.

Ario 4 with DIY Silencer installed between its air inflow controller and air tube.

Nevertheless, noise of the air is transferred trough the air tube outside the aquarium and the tiny sponge in the intake regulator is not enough to muffle it. Therefore, the yellow container pictured in my illustrations was designed to act as a muffler and air purifier with the addition of wool and some active carbon pellets.

My test have proven that Ario series of pumps can well be used as CO2 diffusers with good results. The impeller breaks the CO2 bubbles into spray and after reversing the acrylic cover of the impeller, it acts as a small dome which engages the CO2 to be diffused for longer time.

Ario-4 comes with detailed user manual concerning structural components and installation.

The Ario 4 model is capable of delivering 70 to 200 lt of air per hour at a depth of 50 cm which appropriates it for aquarium from 150 to 300 lt.

Ario-4 Box back with Ario line specs

Of course if you intend to use it as a CO2 diffusor, since CO2 is pressurized the installation depth is not critical.

However, there are a couple of things about the design to consider.
First if you use sand or very fine gravel as a substrate and have fish that are active at the bottom of the aquarium, like Corydoras or Loaches, then avoid installing the Ario pumps in the bottom, because inevitably sand will enter the impeller chamber.
And second the intake sponge needs cleaning very often, otherwise it clogs and water flow is reduced dramatically.

Thank you for viewing.
All Photos © 2007-2017 S.C.Vlachos