That Fish Blog – Aquarium Advice and Information

You may have heard the term refugium if you’re in the aquarium hobby, but do you know what it is and the benefits it can bring to your set-up? A refugium is  essentially a safe area for inverts and macro algae, but it also acts as a biological filter to help control nitrates and phosphates. Refugiums may be part of your sump, a separate hang on back unit, or even another tank plumbed into the display tank system. Generally, it consists of a deep sand bed (DSB), live rock, and macro algae with very slow water flow through the area and a relatively strong light source to support the live plants and inverts you choose to put inside. The light should be in the spectrum between 5,500-8,000k to allow for proper photosynthesis.

Refugium Styles

Let’s take a look at the different styles of refugiums first. One of the most common types is the in-sump refugium. This is a chamber in the sump that has a slow flow (roughly 30% of the water flow from your overflow box) moving through it. This flow rate allows the macro algae and beneficial bacteria to remove waste and nutrients. The best in sump refugium designs are set-up so you can control the flow through the unit, like Trigger Systems Ruby Elite. This style of refugium tends to be one of the most efficient. Read More »