Salty Q&A: Is a Sump the Same as a Refugium?

Question What exactly is the difference between a “sump” and a “refugium” (assuming there is a difference)? These are terms I didn’t hear in my 30-plus years as a freshwater aquarist, but I’ve heard them numerous times since starting my first saltwater tank.” – Submitted by Moira B Answer There is a distinction between a … [Read More]

The Many Possible Purposes of the Saltwater Refugium

“Refugium” is a hobby term that resists easy definition. This is probably so because, unlike most aquarium accoutrements—heaters, powerheads, protein skimmers, lights, etc.—there’s no single, readily identifiable purpose for a refugium. Ask 10 different hobbyists what a refugium is for, and you’re apt to get 10 different answers. Essentially, a refugium is some sort of … [Read More]

Elasmobranch Enthusiasts (Part 3): Modern Husbandry – Filtration

From the ferocious great white shark (Carcharodon carcharias) to the graceful white-spotted eagle ray (Aetobatus narinari), Elasmobranchii are a diverse group of boneless fishes that are circumglobal, inhabiting a diverse array of habitats, temperature ranges, salinity, and niches in the world’s oceans and rivers. It is no wonder that these unique creatures, while usually boasting … [Read More]

The Many Means of Nutrient Export in Marine Aquariums

Dissolved nutrients. Sounds like a good thing, right? After all, every organism needs nutrients in one form or another in order to grow and stay in good health. So why are marine aquarium hobbyists—particularly reefkeepers—seemingly so fixated on keeping the level of dissolved nutrients in their systems as low as possible? To understand this fixation, … [Read More]

Good Reasons to Use a Refugium in Your Reef System

A refugium is a safe haven for algae and invertebrates in a separate tank from the main display aquarium. These organisms provide some distinct advantages to the overall health of a reef aquarium. First off, the critters breeding in the refugium occasionally make their way back to the display and offer healthy snacks for many … [Read More]