Now that you know what a refugium is and how it can benefit your aquarium, it’s time to dive into the practical side—how to set one up! Whether you have a small nano tank or a large reef setup, a refugium can be customized to suit your needs. Let’s go over how to set up a refugium that will work best for your tank.

Types of Refugiums

There are a few different types of refugiums, each suited for different setups:

1. Sump Refugium: This is one of the most popular types. A sump is a secondary tank located below or behind your main aquarium. The refugium section is a separate compartment where you can place macroalgae, live rock, and creatures. Water flows into the sump, passes through the refugium, and then returns to the main tank.
• Pros: Easy to hide, doesn't take up space in your main tank, allows for more equipment like protein skimmers.
• Cons: Requires additional equipment (like a pump), and is often only practical for larger aquariums.
2. Hang-On Back Refugium (HOB): If you don’t have space for a sump, a hang-on refugium attaches to the back of your aquarium. This is a smaller, more compact option for beginners or smaller tanks.
• Pros: Easy to install and maintain, works well for nano tanks or small aquariums.
• Cons: Limited space for macroalgae or creatures, may take up space at the back of your tank.
3. In-Tank Refugium: An in-tank refugium is essentially a section within the main aquarium itself, typically divided by a mesh or acrylic divider. This is a great option for smaller tanks or if you want to integrate the refugium into your display tank.
• Pros: Simple to set up, keeps everything within the main aquarium.
• Cons: Takes up space in your main tank, less room for creatures or macroalgae.

Basic Setup Steps

1. Choose the Right Size and Type: Depending on the space in your aquarium, choose the type of refugium that works best for you. For larger tanks, a sump refugium is ideal, while smaller tanks might benefit from a hang-on or in-tank refugium.
2. Add a Light Source: Macroalgae and other organisms in the refugium need light to grow. A proper lighting setup will encourage healthy algae growth. Use low-wattage, energy-efficient lights that provide a full spectrum, but don’t overpower the refugium.
• Tip: You can use a simple LED light or a specialized refugium light. A 12-hour light cycle mimicking natural daylight works best.
3. Install a Pump: If you’re using a sump refugium, you’ll need a pump to move water from your main tank to the refugium and back. The pump should be appropriately sized for the flow rate you want but avoid too much water movement as it could disrupt the growth of macroalgae.
4. Add Substrate and Live Rock: Adding a layer of sand or gravel to your refugium will help with biological filtration. Live rock is also useful for providing surface area for beneficial bacteria to thrive, breaking down toxins like ammonia and nitrates.
5. Set Up Water Flow: Ensure there’s a gentle water flow within the refugium to keep everything circulating but not too turbulent for the creatures and plants. If using a sump, water should flow steadily through the refugium before returning to the main tank.

Closing Thoughts

Setting up a refugium is a rewarding way to improve water quality and provide a healthy environment for your aquarium’s inhabitants. By choosing the right type of refugium, ensuring proper lighting and water flow, and adding beneficial elements like live rock and substrate, you’ll create a thriving ecosystem that enhances your tank's overall health.

Stay tuned for next week’s installment in our series, where we’ll dive deeper into what goes into a refugium.