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Neptunian Cube

Bring style, simplicity, and cutting-edge marine technology into your home or office with the Neptunian Cube range — the next generation of saltwater aquariums designed for performance and beauty. Combining premium materials, smart filtration design, and minimalist aesthetics, these tanks are engineered to deliver exceptional results for UK reef keepers who demand quality and reliability.

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Have Questions About Neptunian Cube?

We have answers. Get quick help for common questions.

What makes Neptunian Cube aquariums different from other saltwater tanks?
Neptunian Cube aquariums combine premium opti-white glass, ultra-slim weir technology, and a built-in sump system to deliver professional-grade performance in a compact, stylish format. They’re designed for reef hobbyists who want powerful filtration, exceptional clarity, and a minimalistic look — all in one package.
What materials are used in the tank construction?
Every Neptunian Cube is built using ultra-clear, scratch-resistant opti-white glass for the display tank and high-grade acrylic for the included sump. These premium materials ensure maximum clarity, durability, and long-term resilience in saltwater environments.
What additional equipment do I need to buy?
While the tank and sump are included, you’ll need to add your own return pump, protein skimmer, lighting, heater, and circulation pumps depending on your setup. Our team can recommend compatible equipment based on the size of your chosen tank and your livestock goals.
Are Neptunian Cube tanks suitable for reef aquariums?
Absolutely. These tanks are specifically designed for reef and marine systems. The high-clarity glass, efficient overflow, and stable filtration environment make them perfect for coral, invertebrates, and marine fish.
What types of marine life can I keep?
You can house a wide range of livestock, including soft and hard corals, clownfish, gobies, clean-up crews, and other reef-safe fish and invertebrates. Be sure to match your tank size and equipment to the species you plan to keep.
How do I clean the glass without scratching it?
Use a dedicated aquarium-safe algae scraper or magnetic cleaner to avoid scratching the opti-white glass. Avoid using household glass cleaners or abrasive pads.
What sizes are available in the Neptunian Cube range?
The range includes several tank sizes to suit different spaces and experience levels — from nano cubes (~30–60 L) ideal for beginners or desktop setups, to mid-size and larger systems (100 L+) for established reef keepers. Check individual product listings for precise dimensions and specifications.
Do the tanks come with a sump system?
Yes. Every Neptunian Cube includes a custom acrylic sump designed to integrate seamlessly with the tank’s weir box and overflow system. This eliminates the need for additional plumbing or DIY modifications, so you can get started quickly.
How easy is the setup process?
Setup is straightforward thanks to the plug-and-play sump design. Most customers can have their system running in just a few hours. Simply connect the plumbing, fill with saltwater, and add your filtration media before cycling the tank.
Can I use a Neptunian Cube tank for a freshwater setup?
Yes, technically you can, but the design is optimised for saltwater and reef applications. Most customers choose them for marine systems due to their advanced sump and filtration capabilities.
How often do I need to maintain my Neptunian Cube aquarium?
Like all marine aquariums, regular maintenance is essential. Plan for weekly water changes (10–20%), monthly cleaning of the weir and sump, and routine water testing to keep parameters stable. The efficient filtration system makes these tasks easier and helps maintain water quality.
Is the weir box easy to access for cleaning?
Yes — the ultra-thin weir box design not only enhances aesthetics but also allows quick access for cleaning and maintenance. Regular cleaning will keep flow consistent and prevent detritus buildup.

Precision-Engineered for Marine Success

Every Neptunian Cube tank is built around a simple philosophy: maximum performance in a minimal footprint. Crafted from opti-white, scratch-resistant glass, these aquariums provide crystal-clear visibility that lets your corals, fish, and invertebrates shine in natural light. Each tank features what we believe to be the world’s thinnest weir box, ensuring powerful water turnover and effective filtration without compromising the clean, contemporary look of your setup. With a custom-designed acrylic sump included as standard, Neptunian Cube tanks arrive ready to run. Just add your chosen filtration media, lighting, and marine life — everything else is engineered to work straight out of the box.
Precision-Engineered for Marine Success

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