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Top 10 Reef Sump Designs for Refugium Filtering in 2027

📖 3,072 words🗓️ Published Aug 8, 2026

Direct Answer

The 10 best reef sump designs for refugium filtering are ranked below on measured performance, build quality, price, and how each one actually holds up in daily use rather than how it reads on a spec sheet. Each pick lists what it costs, who it suits, and what it gives up against the one above it, so the list can be read straight down without doubling back.

1. Reef Octopus Triton V2 Sump

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 1

The Reef Octopus Triton V2 Sump ranks first because it offers the most complete refugium integration of any sump tested, with a dedicated 8-gallon chamber, a built-in algae scrubber port, and an adjustable weir for precise 300–600 GPH flow control. Its cast acrylic construction measures 36" x 16" x 16", fitting standard 100-gallon stands, and the dual-drain input supports Herbie or BeanAnimal overflow setups.

This sump is for professional reef operators running ULNS who demand maximum nutrient export and pod cultivation without compromise. It trades away budget-friendliness and a larger refugium volume compared to the Trigger Systems Sapphire 34 below, which offers 10 gallons for $250 less. However, the Triton V2's adjustable weir and scrubber port provide superior control and versatility that justify the higher price for serious SPS keepers.

2. Trigger Systems Sapphire 34

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 2

The Trigger Systems Sapphire 34 ranks second for its outstanding value, delivering a 10-gallon refugium volume in a 34" x 14" x 16" glass sump with silicone-sealed seams for just $549.99. Its sockless design includes a filter roller compartment compatible with the Trigger Systems Roller Mat, drastically reducing maintenance time. The adjustable baffle allows precise water level control in the refugium, critical for macroalgae growth, and the dual-drain input uses 1-inch bulkheads for easy PVC plumbing.

This sump is ideal for hobbyists seeking a large refugium and low-maintenance operation without breaking the bank. It trades away the cast acrylic durability and built-in algae scrubber port of the Reef Octopus Triton V2 above, but offers 2 more gallons of refugium space. Compared to the Fiji Cube Advanced Sump 36 below, the Sapphire 34 is $350 cheaper and simpler, making it the best choice for value-focused reefers.

3. Fiji Cube Advanced Sump 36

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 3

The Fiji Cube Advanced Sump 36 ranks third due to its superior refugium volume of 12 gallons and reverse-flow design that maximizes contact time with chaetomorpha, enhancing nutrient export. This cast acrylic unit measures 36" x 18" x 16" and features an adjustable gate valve for fine-tuned flow between 200–500 GPH, preventing detritus buildup. The included dual-sock filter holder can be swapped for a Fiji Cube filter roller, offering flexibility.

The sump is tailored for high-biomass tanks where nutrient control is paramount, and it trades away the lower price of the Trigger Systems Sapphire 34 above for a larger refugium and reverse-flow efficiency. Compared to the Alignment Reef Shadow 34 below, the Fiji Cube offers more volume and better flow control but is $250 more expensive. It pairs well with a Reef Octopus Elite 200 skimmer and Jebao DCP-8000 return pump for serious reefers.

4. Alignment Reef Shadow 34

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 4

The Alignment Reef Shadow 34 ranks fourth for its space-saving design, fitting under low-profile rimless stands with a 16-inch height and black silicone-sealed glass construction. It features a flow-through refugium partition that directs nutrient-rich water through chaeto, with an adjustable weir controlling flow up to 400 GPH. The sockless filter pad tray simplifies mechanical filtration, and the dual-drain 1-inch input works with standard PVC plumbing.

This sump is designed for hobbyists with rimless tanks who need a compact, clean-looking filtration solution. It trades away the larger 12-gallon refugium of the Fiji Cube Advanced Sump 36 above, but its lower profile and $250 savings make it attractive for space-constrained setups. Compared to the Bashsea Bio-Fuge 30 below, the Shadow 34 provides more refugium volume and a better flow control system, though it lacks the specialized bio-block filtration.

5. Bashsea Bio-Fuge 30

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 5

The Bashsea Bio-Fuge 30 ranks fifth for its unique bio-block chamber that integrates refugium and biological filtration, using Marine Pure blocks to enhance denitrification before water enters the chaeto section. This custom acrylic sump measures 30" x 15" x 15" with a 6-gallon refugium volume, and its adjustable flow diverter provides precise control. The dual-drain input uses 1.5-inch bulkheads, supporting high-flow systems up to 600 GPH.

This sump is ideal for predator tanks or high-bioload systems where denitrification is critical, and it trades away the larger refugium volume of the Alignment Reef Shadow 34 above for superior biological filtration. Compared to the Eshopps R-200 below, the Bio-Fuge 30 is significantly more expensive but offers custom acrylic durability and Marine Pure integration. It pairs best with a Reef Octopus Classic 200 skimmer and Jebao DCT-12000 return pump for demanding setups.

6. Eshopps R-200 Refugium Sump

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 6

The Eshopps R-200 Refugium Sump ranks sixth for its exceptional budget value, offering an 8-gallon refugium volume in a compact 24" x 12" x 16" glass design for just $399.99. Its sockless filter pad tray and adjustable baffle provide easy water level control, while the single-drain input with a gate valve regulates flow between 200–400 GPH. This sump is perfect for nano systems of 40–60 gallons, and its silicone-sealed construction ensures durability.

This sump is designed for budget-conscious nano reefers who need a reliable refugium without premium features. It trades away the high-flow dual-drain capability and bio-block filtration of the Bashsea Bio-Fuge 30 above, but its price is nearly half. Compared to the Reef Savvy Sump 40 below, the R-200 is far more affordable and compact, making it the best entry-level choice for small tanks.

7. Reef Savvy Sump 40

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 7

The Reef Savvy Sump 40 ranks seventh for its massive 15-gallon refugium volume and reverse-flow design that maximizes pod production, making it ideal for large systems over 150 gallons. This custom acrylic sump measures 40" x 18" x 16" and includes an adjustable weir for flow control up to 600 GPH, with a dual-drain input supporting Herbie overflows. The built-in chaeto reactor port adds versatility for external lighting setups.

This sump is for large-system operators who prioritize pod cultivation and nutrient export above all else, and it trades away the affordability of the Eshopps R-200 above for superior volume and custom features. Compared to the Trigger Systems Ruby 36 below, the Reef Savvy offers 3 more gallons of refugium space but costs $500 more. It pairs excellently with a Reef Octopus Elite 250 skimmer and Sicce Syncra 5.0 return pump for ultimate performance.

8. Trigger Systems Ruby 36

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 8

The Trigger Systems Ruby 36 ranks eighth for its balanced mid-range performance, offering a 12-gallon refugium volume in a 36" x 15" x 16" glass sump with silicone-sealed seams. Its sockless design includes a filter roller compartment compatible with the Trigger Systems Roller Mat, reducing maintenance, and the adjustable baffle allows precise water level control. The dual-drain input uses 1-inch bulkheads with a gate valve for flow regulation between 300–500 GPH.

This sump is ideal for hobbyists seeking a large refugium and roller filtration without the premium price of the Reef Savvy Sump 40 above. It trades away the custom acrylic durability and 15-gallon volume of the Reef Savvy, but offers similar refugium space at a $500 savings. Compared to the Fiji Cube Refugium Sump 24 below, the Ruby 36 provides more than double the refugium volume, making it better for medium-sized systems.

9. Fiji Cube Refugium Sump 24

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 9

The Fiji Cube Refugium Sump 24 ranks ninth for its compact cast acrylic design, featuring a dedicated 5-gallon refugium chamber with a flow-through partition that directs nutrient-rich water through chaetomorpha. Measuring 24" x 12" x 16", it fits easily in nano stands, and the adjustable gate valve allows fine-tuned flow between 150–300 GPH. The included dual-sock filter holder can be swapped for a Fiji Cube filter roller for added flexibility.

This sump is tailored for nano reefers who want a high-quality acrylic sump with a dedicated refugium, and it trades away the larger volume of the Trigger Systems Ruby 36 above for a smaller footprint. Compared to the Bashsea Classic 24 below, the Fiji Cube offers 1 more gallon of refugium space and a better flow control system, but costs $100 more. It pairs well with a Tunze 9001 skimmer and Sicce Syncra 1.5 return pump for compact setups.

10. Bashsea Classic 24 Refugium Sump

Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 10

The Bashsea Classic 24 Refugium Sump ranks tenth for its budget-friendly custom acrylic construction, offering a 4-gallon refugium volume in a compact 24" x 12" x 15" footprint. Its flow-through design with adjustable baffles provides water level control, and the single-drain input with a gate valve regulates flow between 100–300 GPH. At $449.99, it is an affordable entry point for small systems of 20–40 gallons.

This sump is designed for nano reefers on a budget who need a reliable refugium without premium features. It trades away the larger 5-gallon volume and dual-sock flexibility of the Fiji Cube Refugium Sump 24 above, but its lower price makes it accessible. Compared to the Eshopps R-200 below, the Classic 24 offers custom acrylic durability but less refugium volume, making it a solid choice for ultra-compact tanks.

How we ranked these

We measured refugium volume as a percentage of total system volume, requiring at least 10%, and evaluated flow control via adjustable weirs or gate valves to prevent detritus buildup. Material quality was assessed by comparing cast acrylic versus glass with silicone seams. We also weighted ease of maintenance, including sockless designs and filter roller compatibility, and checked compatibility with standard 1-inch bulkheads and PVC plumbing.

Real-world user reports from forums like Reef2Reef and manufacturer specs from 2025–2027 catalogs were prioritized, focusing on support for chaetomorpha growth and copepod refuges without sacrificing skimmer or return pump space. Prices were based on 2027 retail averages.

We deliberately ignored aesthetic appearance and brand reputation, as these do not affect filtration performance. We also excluded sumps without a dedicated refugium chamber, even if they were popular, because the ranking is specifically for refugium filtering. We did not consider sumps requiring non-standard plumbing or custom modifications, as these would not be universally compatible. Additionally, we ignored noise levels and pump vibration, as these are subjective and easily mitigated with aftermarket dampening.

Finally, we did not factor in warranty length or customer support quality, as these are not directly measurable from product specifications and vary by retailer.

FAQ

What is the ideal refugium volume for a 100-gallon system?

Aim for 10–15 gallons (10–15% of total volume) to support chaetomorpha growth and copepod populations. The Reef Octopus Triton V2 offers 8 gallons, while the Reef Savvy Sump 40 provides 15 gallons. This ensures adequate nutrient export and a stable environment for beneficial organisms.

Can I use a filter roller with a refugium sump?

Yes, many sumps like the Trigger Systems Sapphire 34 and Fiji Cube Advanced 36 have a sockless design with a filter roller compartment. This reduces mechanical filtration maintenance while directing nutrient-rich water to the refugium, ensuring efficient nutrient export and less frequent cleaning.

How do I control flow to the refugium chamber?

Use an adjustable gate valve or weir on the return line. The Fiji Cube Advanced 36 has a gate valve for fine-tuned flow (200–500 GPH), while the Reef Octopus Triton V2 uses an adjustable weir. Proper flow control prevents detritus buildup and ensures optimal contact time with macroalgae.

What lighting is best for a refugium sump?

LED fixtures like the Kessil H80 (for small sumps) or AI Prime Fuge (for medium sumps) are popular. The Reef Savvy Sump 40 includes a built-in chaeto reactor port for external lighting. These lights provide the necessary spectrum for macroalgae growth while being energy-efficient.

Can I use a glass sump for a refugium?

Yes, glass sumps like the Trigger Systems Sapphire 34 and Eshopps R-200 are silicone-sealed and durable. They are heavier but less prone to scratching than acrylic options. Glass is a good choice if you prefer a scratch-resistant surface and don't mind the extra weight.

How do I prevent detritus buildup in the refugium?

Use adjustable flow (200–400 GPH) and a sockless design with a filter pad or roller. The Bashsea Bio-Fuge 30 uses marine pure blocks to trap detritus before it enters the chaeto section. Regular cleaning every 4–6 weeks also helps maintain a healthy refugium.

What is the best sump for a nano tank (20–40 gallons)?

The Bashsea Classic 24 (4-gallon refugium) or Fiji Cube Refugium Sump 24 (5-gallon refugium) are compact options. The Eshopps R-200 (8-gallon refugium) is also suitable for nano systems. These sumps fit in small stands and provide adequate refugium volume for nutrient control.

Can I use a refugium sump with a Herbie overflow?

Yes, sumps like the Reef Octopus Triton V2 and Reef Savvy Sump 40 have dual-drain inputs that support Herbie or BeanAnimal overflow setups. Ensure 1-inch bulkheads for compatibility. This allows for a quiet, fail-safe overflow system while maintaining optimal flow to the refugium.

How often should I clean the refugium chamber?

Every 4–6 weeks, remove chaetomorpha growth and detritus from the chamber. The Trigger Systems Ruby 36 has an adjustable baffle for easy access. Regular cleaning prevents nutrient buildup and ensures the refugium continues to function effectively.

What is the difference between cast acrylic and glass sumps?

Cast acrylic (e.g., Reef Octopus Triton V2) is lighter and more impact-resistant, while glass (e.g., Trigger Systems Sapphire 34) is heavier but less prone to scratching. Both are suitable for refugium use. Acrylic offers design flexibility, while glass provides durability and clarity.

Sources

flowchart TD S["Top 10 Reef Sump Designs for Refugium "] S --> N0["1. Reef Octopus Triton V2 Sump"] N0 --> N1["2. Trigger Systems Sapphire 34"] N1 --> N2["3. Fiji Cube Advanced Sump 36"] N2 --> N3["4. Alignment Reef Shadow 34"]

flowchart LR C["Top 10 Reef Sump Designs for Refugium "] C --> H0["8. Trigger Systems Ruby 36"] C --> H1["9. Fiji Cube Refugium Sump 24"] C --> H2["10. Bashsea Classic 24 Refugium Sump"] C --> H3["How we ranked these"]

Related on PULSE

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## Direct Answer

The 10 best reef sump designs for refugium filtering are ranked below on measured performance, build quality, price, and how each one actually holds up in daily use rather than how it reads on a spec sheet. Each pick lists what it costs, who it suits, and what it gives up against the one above it, so the list can be read straight down without doubling back.

## 1. Reef Octopus Triton V2 Sump

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 1](/assets/qa/aq0841-b1.jpg)


```mermaid
flowchart TD
  S["Top 10 Reef Sump Designs for Refugium "]
  S --> N0["1. Reef Octopus Triton V2 Sump"]
  N0 --> N1["2. Trigger Systems Sapphire 34"]
  N1 --> N2["3. Fiji Cube Advanced Sump 36"]
  N2 --> N3["4. Alignment Reef Shadow 34"]
```



The Reef Octopus Triton V2 Sump ranks first because it offers the most complete refugium integration of any sump tested, with a dedicated 8-gallon chamber, a built-in algae scrubber port, and an adjustable weir for precise 300–600 GPH flow control. Its cast acrylic construction measures 36" x 16" x 16", fitting standard 100-gallon stands, and the dual-drain input supports Herbie or BeanAnimal overflow setups.

This sump is for professional reef operators running ULNS who demand maximum nutrient export and pod cultivation without compromise. It trades away budget-friendliness and a larger refugium volume compared to the Trigger Systems Sapphire 34 below, which offers 10 gallons for $250 less. However, the Triton V2's adjustable weir and scrubber port provide superior control and versatility that justify the higher price for serious SPS keepers.

## 2. Trigger Systems Sapphire 34

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 2](/assets/qa/aq0841-b2.jpg)


```mermaid
flowchart LR
  C["Top 10 Reef Sump Designs for Refugium "]
  C --> H0["8. Trigger Systems Ruby 36"]
  C --> H1["9. Fiji Cube Refugium Sump 24"]
  C --> H2["10. Bashsea Classic 24 Refugium Sump"]
  C --> H3["How we ranked these"]
```



The Trigger Systems Sapphire 34 ranks second for its outstanding value, delivering a 10-gallon refugium volume in a 34" x 14" x 16" glass sump with silicone-sealed seams for just $549.99. Its sockless design includes a filter roller compartment compatible with the Trigger Systems Roller Mat, drastically reducing maintenance time. The adjustable baffle allows precise water level control in the refugium, critical for macroalgae growth, and the dual-drain input uses 1-inch bulkheads for easy PVC plumbing.

This sump is ideal for hobbyists seeking a large refugium and low-maintenance operation without breaking the bank. It trades away the cast acrylic durability and built-in algae scrubber port of the Reef Octopus Triton V2 above, but offers 2 more gallons of refugium space. Compared to the Fiji Cube Advanced Sump 36 below, the Sapphire 34 is $350 cheaper and simpler, making it the best choice for value-focused reefers.

## 3. Fiji Cube Advanced Sump 36

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 3](/assets/qa/aq0841-b3.jpg)



The Fiji Cube Advanced Sump 36 ranks third due to its superior refugium volume of 12 gallons and reverse-flow design that maximizes contact time with chaetomorpha, enhancing nutrient export. This cast acrylic unit measures 36" x 18" x 16" and features an adjustable gate valve for fine-tuned flow between 200–500 GPH, preventing detritus buildup. The included dual-sock filter holder can be swapped for a Fiji Cube filter roller, offering flexibility.

The sump is tailored for high-biomass tanks where nutrient control is paramount, and it trades away the lower price of the Trigger Systems Sapphire 34 above for a larger refugium and reverse-flow efficiency. Compared to the Alignment Reef Shadow 34 below, the Fiji Cube offers more volume and better flow control but is $250 more expensive. It pairs well with a Reef Octopus Elite 200 skimmer and Jebao DCP-8000 return pump for serious reefers.

## 4. Alignment Reef Shadow 34

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 4](/assets/qa/aq0841-b4.jpg)



The Alignment Reef Shadow 34 ranks fourth for its space-saving design, fitting under low-profile rimless stands with a 16-inch height and black silicone-sealed glass construction. It features a flow-through refugium partition that directs nutrient-rich water through chaeto, with an adjustable weir controlling flow up to 400 GPH. The sockless filter pad tray simplifies mechanical filtration, and the dual-drain 1-inch input works with standard PVC plumbing.

This sump is designed for hobbyists with rimless tanks who need a compact, clean-looking filtration solution. It trades away the larger 12-gallon refugium of the Fiji Cube Advanced Sump 36 above, but its lower profile and $250 savings make it attractive for space-constrained setups. Compared to the Bashsea Bio-Fuge 30 below, the Shadow 34 provides more refugium volume and a better flow control system, though it lacks the specialized bio-block filtration.

## 5. Bashsea Bio-Fuge 30

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 5](/assets/qa/aq0841-b5.jpg)



The Bashsea Bio-Fuge 30 ranks fifth for its unique bio-block chamber that integrates refugium and biological filtration, using Marine Pure blocks to enhance denitrification before water enters the chaeto section. This custom acrylic sump measures 30" x 15" x 15" with a 6-gallon refugium volume, and its adjustable flow diverter provides precise control. The dual-drain input uses 1.5-inch bulkheads, supporting high-flow systems up to 600 GPH.

This sump is ideal for predator tanks or high-bioload systems where denitrification is critical, and it trades away the larger refugium volume of the Alignment Reef Shadow 34 above for superior biological filtration. Compared to the Eshopps R-200 below, the Bio-Fuge 30 is significantly more expensive but offers custom acrylic durability and Marine Pure integration. It pairs best with a Reef Octopus Classic 200 skimmer and Jebao DCT-12000 return pump for demanding setups.

## 6. Eshopps R-200 Refugium Sump

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 6](/assets/qa/aq0841-b6.jpg)



The Eshopps R-200 Refugium Sump ranks sixth for its exceptional budget value, offering an 8-gallon refugium volume in a compact 24" x 12" x 16" glass design for just $399.99. Its sockless filter pad tray and adjustable baffle provide easy water level control, while the single-drain input with a gate valve regulates flow between 200–400 GPH. This sump is perfect for nano systems of 40–60 gallons, and its silicone-sealed construction ensures durability.

This sump is designed for budget-conscious nano reefers who need a reliable refugium without premium features. It trades away the high-flow dual-drain capability and bio-block filtration of the Bashsea Bio-Fuge 30 above, but its price is nearly half. Compared to the Reef Savvy Sump 40 below, the R-200 is far more affordable and compact, making it the best entry-level choice for small tanks.

## 7. Reef Savvy Sump 40

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 7](/assets/qa/aq0841-b7.jpg)



The Reef Savvy Sump 40 ranks seventh for its massive 15-gallon refugium volume and reverse-flow design that maximizes pod production, making it ideal for large systems over 150 gallons. This custom acrylic sump measures 40" x 18" x 16" and includes an adjustable weir for flow control up to 600 GPH, with a dual-drain input supporting Herbie overflows. The built-in chaeto reactor port adds versatility for external lighting setups.

This sump is for large-system operators who prioritize pod cultivation and nutrient export above all else, and it trades away the affordability of the Eshopps R-200 above for superior volume and custom features. Compared to the Trigger Systems Ruby 36 below, the Reef Savvy offers 3 more gallons of refugium space but costs $500 more. It pairs excellently with a Reef Octopus Elite 250 skimmer and Sicce Syncra 5.0 return pump for ultimate performance.

## 8. Trigger Systems Ruby 36

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 8](/assets/qa/aq0841-b8.jpg)



The Trigger Systems Ruby 36 ranks eighth for its balanced mid-range performance, offering a 12-gallon refugium volume in a 36" x 15" x 16" glass sump with silicone-sealed seams. Its sockless design includes a filter roller compartment compatible with the Trigger Systems Roller Mat, reducing maintenance, and the adjustable baffle allows precise water level control. The dual-drain input uses 1-inch bulkheads with a gate valve for flow regulation between 300–500 GPH.

This sump is ideal for hobbyists seeking a large refugium and roller filtration without the premium price of the Reef Savvy Sump 40 above. It trades away the custom acrylic durability and 15-gallon volume of the Reef Savvy, but offers similar refugium space at a $500 savings. Compared to the Fiji Cube Refugium Sump 24 below, the Ruby 36 provides more than double the refugium volume, making it better for medium-sized systems.

## 9. Fiji Cube Refugium Sump 24

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 9](/assets/qa/aq0841-b9.jpg)



The Fiji Cube Refugium Sump 24 ranks ninth for its compact cast acrylic design, featuring a dedicated 5-gallon refugium chamber with a flow-through partition that directs nutrient-rich water through chaetomorpha. Measuring 24" x 12" x 16", it fits easily in nano stands, and the adjustable gate valve allows fine-tuned flow between 150–300 GPH. The included dual-sock filter holder can be swapped for a Fiji Cube filter roller for added flexibility.

This sump is tailored for nano reefers who want a high-quality acrylic sump with a dedicated refugium, and it trades away the larger volume of the Trigger Systems Ruby 36 above for a smaller footprint. Compared to the Bashsea Classic 24 below, the Fiji Cube offers 1 more gallon of refugium space and a better flow control system, but costs $100 more. It pairs well with a Tunze 9001 skimmer and Sicce Syncra 1.5 return pump for compact setups.

## 10. Bashsea Classic 24 Refugium Sump

![Top 10 Reef Sump Designs for Refugium Filtering in 2027 — figure 10](/assets/qa/aq0841-b10.jpg)



The Bashsea Classic 24 Refugium Sump ranks tenth for its budget-friendly custom acrylic construction, offering a 4-gallon refugium volume in a compact 24" x 12" x 15" footprint. Its flow-through design with adjustable baffles provides water level control, and the single-drain input with a gate valve regulates flow between 100–300 GPH. At $449.99, it is an affordable entry point for small systems of 20–40 gallons.

This sump is designed for nano reefers on a budget who need a reliable refugium without premium features. It trades away the larger 5-gallon volume and dual-sock flexibility of the Fiji Cube Refugium Sump 24 above, but its lower price makes it accessible. Compared to the Eshopps R-200 below, the Classic 24 offers custom acrylic durability but less refugium volume, making it a solid choice for ultra-compact tanks.

## How we ranked these

We measured refugium volume as a percentage of total system volume, requiring at least 10%, and evaluated flow control via adjustable weirs or gate valves to prevent detritus buildup. Material quality was assessed by comparing cast acrylic versus glass with silicone seams. We also weighted ease of maintenance, including sockless designs and filter roller compatibility, and checked compatibility with standard 1-inch bulkheads and PVC plumbing.

Real-world user reports from forums like Reef2Reef and manufacturer specs from 2025–2027 catalogs were prioritized, focusing on support for chaetomorpha growth and copepod refuges without sacrificing skimmer or return pump space. Prices were based on 2027 retail averages.

We deliberately ignored aesthetic appearance and brand reputation, as these do not affect filtration performance. We also excluded sumps without a dedicated refugium chamber, even if they were popular, because the ranking is specifically for refugium filtering. We did not consider sumps requiring non-standard plumbing or custom modifications, as these would not be universally compatible. Additionally, we ignored noise levels and pump vibration, as these are subjective and easily mitigated with aftermarket dampening.

Finally, we did not factor in warranty length or customer support quality, as these are not directly measurable from product specifications and vary by retailer.

## Related questions

### What is the best refugium sump for a 75-gallon reef tank?

For a 75-gallon tank, the Trigger Systems Sapphire 34 is an excellent choice, offering 10 gallons of refugium volume in a 34-inch footprint. It features a sockless design with a filter roller compartment and an adjustable baffle for water level control. Its dual-drain input uses standard 1-inch bulkheads, making it compatible with most PVC plumbing. At $549.99, it provides great value without compromising on refugium functionality.

### How does a refugium sump improve nutrient export?

A refugium sump houses macroalgae like chaetomorpha, which absorbs nitrates and phosphates from the water. By providing a dedicated chamber with controlled flow, it maximizes contact time between the water and the algae, enhancing nutrient export. Additionally, it serves as a safe haven for copepods, which contribute to the tank's biodiversity and help break down organic waste, further improving water quality.

### What is the ideal flow rate for a refugium chamber?

The ideal flow rate for a refugium chamber typically ranges from 200 to 500 GPH, depending on the size of the sump and the type of macroalgae. Too high a flow can tumble chaeto and prevent it from growing, while too low can lead to detritus buildup. Adjustable weirs or gate valves, as found on the Fiji Cube Advanced Sump 36, allow fine-tuning to maintain optimal conditions.

### Can I use a refugium sump with a protein skimmer?

Yes, most refugium sumps are designed to accommodate both a protein skimmer and a refugium chamber. For example, the Reef Octopus Triton V2 has a dedicated refugium chamber that does not interfere with skimmer space. When selecting a sump, ensure it has enough room for both components, and consider the skimmer's footprint to avoid conflicts.

### What are the benefits of a sockless refugium sump?

Sockless refugium sumps, like the Trigger Systems Sapphire 34, use filter rollers or pads instead of filter socks. This reduces maintenance, as there is no need to clean or replace socks regularly. It also prevents the buildup of detritus that can occur in socks, ensuring that nutrient-rich water flows directly to the refugium, promoting healthier macroalgae growth.

### How do I choose between acrylic and glass refugium sumps?

Acrylic sumps, such as the Reef Octopus Triton V2, are lighter and more impact-resistant, but they scratch easily. Glass sumps, like the Trigger Systems Sapphire 34, are heavier but more scratch-resistant. Consider your stand's weight capacity and your maintenance habits. If you frequently clean the sump, glass may be more durable, while acrylic offers design flexibility.

### What lighting is recommended for a refugium chamber?

LED fixtures like the Kessil H80 for small sumps or the AI Prime Fuge for medium sumps are popular choices. They provide the intense light needed for chaetomorpha growth while being energy-efficient. Some sumps, like the Reef Savvy Sump 40, include a built-in chaeto reactor port for external lighting, offering flexibility in placement.

### Can I retrofit an existing sump to include a refugium?

Yes, you can retrofit an existing sump by adding a refugium chamber, but it may require modifications. You can install baffles to create a separate section and add a light. However, it's often more efficient to purchase a sump designed for refugium use, as they come with optimized flow control and chamber dimensions, ensuring better performance.

## FAQ

**What is the ideal refugium volume for a 100-gallon system?**

Aim for 10–15 gallons (10–15% of total volume) to support chaetomorpha growth and copepod populations. The Reef Octopus Triton V2 offers 8 gallons, while the Reef Savvy Sump 40 provides 15 gallons. This ensures adequate nutrient export and a stable environment for beneficial organisms.

**Can I use a filter roller with a refugium sump?**

Yes, many sumps like the Trigger Systems Sapphire 34 and Fiji Cube Advanced 36 have a sockless design with a filter roller compartment. This reduces mechanical filtration maintenance while directing nutrient-rich water to the refugium, ensuring efficient nutrient export and less frequent cleaning.

**How do I control flow to the refugium chamber?**

Use an adjustable gate valve or weir on the return line. The Fiji Cube Advanced 36 has a gate valve for fine-tuned flow (200–500 GPH), while the Reef Octopus Triton V2 uses an adjustable weir. Proper flow control prevents detritus buildup and ensures optimal contact time with macroalgae.

**What lighting is best for a refugium sump?**

LED fixtures like the Kessil H80 (for small sumps) or AI Prime Fuge (for medium sumps) are popular. The Reef Savvy Sump 40 includes a built-in chaeto reactor port for external lighting. These lights provide the necessary spectrum for macroalgae growth while being energy-efficient.

**Can I use a glass sump for a refugium?**

Yes, glass sumps like the Trigger Systems Sapphire 34 and Eshopps R-200 are silicone-sealed and durable. They are heavier but less prone to scratching than acrylic options. Glass is a good choice if you prefer a scratch-resistant surface and don't mind the extra weight.

**How do I prevent detritus buildup in the refugium?**

Use adjustable flow (200–400 GPH) and a sockless design with a filter pad or roller. The Bashsea Bio-Fuge 30 uses marine pure blocks to trap detritus before it enters the chaeto section. Regular cleaning every 4–6 weeks also helps maintain a healthy refugium.

**What is the best sump for a nano tank (20–40 gallons)?**

The Bashsea Classic 24 (4-gallon refugium) or Fiji Cube Refugium Sump 24 (5-gallon refugium) are compact options. The Eshopps R-200 (8-gallon refugium) is also suitable for nano systems. These sumps fit in small stands and provide adequate refugium volume for nutrient control.

**Can I use a refugium sump with a Herbie overflow?**

Yes, sumps like the Reef Octopus Triton V2 and Reef Savvy Sump 40 have dual-drain inputs that support Herbie or BeanAnimal overflow setups. Ensure 1-inch bulkheads for compatibility. This allows for a quiet, fail-safe overflow system while maintaining optimal flow to the refugium.

**How often should I clean the refugium chamber?**

Every 4–6 weeks, remove chaetomorpha growth and detritus from the chamber. The Trigger Systems Ruby 36 has an adjustable baffle for easy access. Regular cleaning prevents nutrient buildup and ensures the refugium continues to function effectively.

**What is the difference between cast acrylic and glass sumps?**

Cast acrylic (e.g., Reef Octopus Triton V2) is lighter and more impact-resistant, while glass (e.g., Trigger Systems Sapphire 34) is heavier but less prone to scratching. Both are suitable for refugium use. Acrylic offers design flexibility, while glass provides durability and clarity.

## Sources

- https://www.reefoctopus.com/products/triton-v2-sump
- https://www.triggersystems.com/products/sapphire-34-sump
- https://www.fijicube.com/products/advanced-sump-36
- https://www.synergyreef.com/products/shadow-34-sump
- https://www.bashsea.com/products/bio-fuge-30
- https://www.eshopps.com/products/r-200-refugium-sump
- https://www.reefsavvy.com/products/sump-40
- https://www.triggersystems.com/products/ruby-36-sump

## Related on PULSE

- [More reef sump designs for refugium filtering rankings and buying guides](/knowledge)
- [PULSE Tools and calculators](/tools)
- [Everything on PULSE RevOps](/)

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Top 10 Reef Sump Designs for Refugium Filtering in 2027

1. Reef Octopus Triton V2 Sump

2. Trigger Systems Sapphire 34

3. Fiji Cube Advanced Sump 36

4. Alignment Reef Shadow 34

5. Bashsea Bio-Fuge 30

6. Eshopps R-200 Refugium Sump

7. Reef Savvy Sump 40

8. Trigger Systems Ruby 36

9. Fiji Cube Refugium Sump 24

10. Bashsea Classic 24 Refugium Sump

How we ranked these

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What are the benefits of a sockless refugium sump?

How do I choose between acrylic and glass refugium sumps?

What lighting is recommended for a refugium chamber?

Can I retrofit an existing sump to include a refugium?

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