All In One Aquariums for Saltwater Enthusiasts

All in one (AIO) aquariums have become increasingly popular, especially for those new to the saltwater aquarium hobby. These aquariums offer a simplified, cost-effective solution for setting up a saltwater tank. But what exactly makes them so special, and are they the right choice for you? This comprehensive guide will explore everything you need about all-in-one saltwater aquariums.

What is an All-In-One Aquarium?

All-in-one aquariums are self-contained systems with all the essential equipment concealed and integrated into a single sleek tank. This includes protein skimmers, pumps, heaters, and filtration media. It eliminates the need for bulky external hardware.

The main components of an AIO saltwater aquarium include:

Integrated overflow – This is located in the back corner and directs water into the filter area below. It maintains consistent water volume in the display area.

Built-in filtration – This is the heart of the system. Water flows through various stages like mechanical, chemical, and biological filtration to remove waste and maintain water quality.

Protein skimmer – An efficient protein skimmer is critical for saltwater tanks. It removes dissolved organic compounds before they break down into nitrogenous waste.

Return pump – Once filtered, the water is returned to the display tank using a high-quality return pump. This also ensures proper circulation.

Heater – Maintaining a stable, ideal temperature is essential for marine organisms. A built-in heater eliminates temperature fluctuations.

Lighting – Many AIOs now feature state-of-the-art LED lighting perfect for coral growth and aesthetics.

This innovative configuration allows for a compact, streamlined system that can fit into small spaces. It also creates a seamless, modern look compared to tanks crammed with equipment.

How Does an All-In-One Saltwater Tank Work?

To understand why AIO aquariums are revolutionary, it helps to visualize how water flows through the system:

  1. Overflow – Water from the display section enters the overflow box at the back top portion of the tank. This keeps the water at a consistent level, preventing flooding.
  2. Mechanical filtration – Foam, sponges, or filter socks capture debris, preventing clogging of delicate equipment.
  3. Protein skimming – Air is injected into a conical chamber, allowing oils and proteins to bind to bubbles. The foam is then separated and discarded.
  4. Chemical filtration – Activated carbon or phosphate media removes dissolved contaminants and manages nutrients.
  5. Biological filtration – Substrates like bio-balls or live rock give beneficial bacteria space to colonize and break down waste.
  6. Return pump – Filtered water is pumped back into the display tank using either a powerhead, closed loop system or internal wavemakers.
  7. Heater and temperature control – Thermostats regulate heat to maintain optimum temperatures.
  8. Lighting – Energy-efficient LEDs simulate sunlight patterns to support corals and marine life.

This “closed loop” system allows water to continually recirculate through various stages of filtration, eliminating waste and promoting a healthy saltwater habitat.

Pros and Cons of All-In-One Aquariums

All-in-one aquariums come with several advantages along with some potential limitations:

Advantages of AIO Saltwater Tanks

  • Convenience – With all components seamlessly built-in, set-up and maintenance are much easier than sump systems.
  • Beginner-friendly – The simplified process allows those new to the hobby to have success with a marine tank.
  • Size – Compact all-in-one designs are perfect for small spaces, apartments or offices.
  • Appearance – The clean, modern aesthetics make the tank a beautiful focal point.
  • Cost – AIO aquariums are generally more affordable than custom systems, especially smaller nano models.
  • Quiet – These systems operate silently with equipment enclosed in the back chamber.

Potential Limitations

  • Limited space for equipment – The confined filtration area may restrict upgrades or additions.
  • Accessibility – Filtration compartments are harder to reach compared to external sumps.
  • Reduced water volume – Space taken up by hardware lowers overall water volume.
  • Pre-configured – Options for customization are limited due to the integrated design.
  • Potential for leakage – More seams and bulkheads increase chances of leaks if defects occur.
  • Difficult repair – Malfunctioning parts can be challenging to replace within the enclosed area.

With some creative aquascaping and planning, these limitations can often be overcome or minimized. The benefits tend to outweigh the drawbacks for most hobbyists.

Are All-In-One Aquariums Suitable for Saltwater Tanks?

All-in-one aquariums can certainly succeed as saltwater tanks but do come with some special considerations. Some key factors when using an AIO for marine life include:

  • Ample filtration – Toxins easily impact the smaller water volume, so robust mechanical, chemical and biological filtration is necessary.
  • Efficient protein skimming – A good skimmer appropriate for the tank size will remove dissolved organics before they degrade water quality.
  • Adequate circulation – Careful placement of powerheads is needed to prevent dead spots and ensure proper delivery of nutrients.
  • Stable parameters – Fluctuating salinity, temperature, nutrients or pH will rapidly stress inhabitants.
  • Appropriate lighting – Reef-safe LEDs that won’t promote algae growth are ideal for many corals.
  • Low bioload – Avoid overstocking and keep species with small footprints suitable for the tank size.
  • Frequent testing – Monitor ammonia, nitrate, nitrite, pH, alkalinity, calcium, and other parameters often.
  • Regular maintenance – Weekly water changes, filter cleanings, glass algae removal and equipment calibration are necessary.

With close attention to these factors, AIO tanks can thrive as saltwater habitats. The fundamental filtration and system requirements for marine species can all be achieved with innovative all-in-one designs.

Size Options for All-In-One Saltwater Aquariums

All-in-one aquariums are available in various sizes to suit any space. Here’s an overview of some of the most common AIO dimensions perfect for saltwater:

Nano AIO Tanks (Under 25 Gallons)

Nano cubes as small as 3 or 5 gallons up to 20-gallon systems are ideal for office desks or small stands. Even in the most compact areas, they allow you a slice of marine life. Nano AIOs can fit into the most constrained spaces with their tiny footprints.

While limiting, these pint-sized aquariums are perfect for hosting a few small fish species or a nano reef structure. The Waterbox Cube 10 and Coralife Biocube 16 are great starter options. Use their diminutive size to your advantage by creating a unique biotope aquascape.

Medium AIO Tanks (25-50 Gallons)

The 25 to 50 gallon range allows for more creative freedom in stocking and aquascaping. You can comfortably house a community of fish, soft corals, and LPS corals. The Red Sea Max E-Series and Waterbox Marine X Series are excellent mid-sized AIO picks.

Consider mixing a pair of clownfish or goby with some vibrant LPS corals like trumpet or torch corals. The extra gallons provide more stable conditions compared to pint-sized nano cubes.

Large AIO Tanks (50-90 Gallons)

For those with ample space, larger all-in-one systems over 50 gallons give you the most flexibility. Go for bolder aquascapes with a diverse reef structure and active, interesting fish like tangs, angels, and maybe even some anemones.

The Waterbox Reefer XL and Red Sea Reefer Series are well-designed choices in this size range. Take advantage of the bigger volume to create a thriving mixed reef tank that will be the showpiece of your home.

Extra Large AIO Tanks (90-150 Gallons)

Once you move past 100 gallons, the possibilities become nearly endless. Large all-in-one aquariums allow advanced hobbyists to create show-stopper reef exhibits in their homes.

These monsters provide enough capacity for large, stunning coral colonies like acropora or montipora. You can even keep more delicate species like SPS corals under perfect conditions.

Some epic AIO options in this range are the Waterbox frag tank, Innovative Marine Skkye, and the Red Sea reefer XL series. A tank over 100 gallons allows you to keep fish that need more space like tangs, triggers, angels, and puffers.

Aim high with your aquascaping dreams in extra large all-in-one setups. You could have a tranquil oasis with undulating fields of leather corals or an underwater cliff face with vibrant colonies of birds nest coral. Just be ready for the increased maintenance and equipment demands of massive tanks.

Custom All-In-One Aquariums

For nearly unlimited possibilities, many retailers offer fully customizable AIO tanks. To create a fully tailored saltwater habitat, you can select the dimensions, filtration types, lighting, and other options.

Waterbox Aquariums is one company leading the way in bespoke AIO designs. Their configurator allows you to input exact tank measurements and your choice of filtration method, lighting, and lid options. You can bring your unique vision to life!

Alternatives to All-in-One Saltwater Aquariums

While AIO tanks offer distinct advantages, they aren’t the only route to a successful saltwater aquarium. Here are some other potential setups to consider:

Traditional Fish-Only Systems

The classic approach combines a basic glass aquarium with external canister filters and protein skimmers. This more modular design allows for great customization and expansion. For fish-only marine tanks, traditional configurations get the job done.

Sump-Based Reef Systems

Serious reef aquarists often prefer using a sump to increase water volume and house equipment externally. High-end reef ready tanks connect to wet-dry trickle filters below, offering expanded filtration capabilities. Sumps provide more power and flexibility for advanced coral keepers.

Pico Reef Aquariums

At just 2-5 gallons, these tiny tanks let you create a nano-reef or keep a few marine creatures with a minimal footprint. Small cubes like the AquaMaxx or Picotope require meticulous care but can thrive with specialty corals.

Rimless or Low Iron Tanks

For jaw-dropping aesthetics, rimless Starphire glass tanks offer absolutely pristine clarity. While expensive, their crisp viewing and sleek profiles create a contemporary showpiece. Red Sea and Waterbox make stunning rimless systems.

DIY Saltwater Aquarium Builds

If you like getting hands-on, building a custom tank lets you craft exactly the marine habitat you envision. Combine unusual shapes, dimensions and equipment configurations for a one-of-a-kind aquarium.

Choosing the Best All-In-One Aquarium Brands

With many manufacturers now producing AIO systems, deciding which brand to trust can be tricky. Based on extensive customer reviews and product research, these brands consistently rise to the top:

Waterbox Aquariums

Regarded as the pioneer of all-in-one tanks, Waterbox delivers premium quality rimless aquariums in many sizes. Their filtration systems are highly customizable, and their Starphire crystal clear glass is simply stunning.

Red Sea Reef Systems

Red Sea is a leader in complete saltwater ecosystem tanks. Their plug-and-play Reefer series features advanced filtration and reef-ready lighting. Red Sea also offers expansive customization abilities.

Innovative Marine

Innovative Marine specializes in nanos but makes larger AIO setups like the Skkye and Nuvo Fusion series. Their tanks feature crisp silicone work, rimless open-top models and complete biological filtration.


The original BioCube aquariums made AIO tanks a mainstream hit. Coralife’s cubes remain budget-friendly options for saltwater beginners. Models like the Biocube 32 incorporate vital features into a compact package.

JBJ Lighting

Another early pioneer in nano cubes, JBJ Lighting produces the venerable NanoCube. These affordable, user-friendly all-in-one tanks are ideal starter models for nano reefs. JBJ also makes the rimless Aquarium AIO systems.

Key Components: What to Look for in AIO Tanks

When comparing all-in-one aquarium options, keep an eye out for these vital components:

Sufficient Filtration Capacity

Ensure the filtration is robust enough for the tank size, with room for expansion. Multiple mechanical, chemical and biological stages are ideal.

Quiet, Energy Efficient Pumps

High-quality return pumps that won’t burn out quickly or make loud humming noises. Choose pumps sized for optimal turnover.

Effective Built-In Protein Skimming

A good skimmer appropriate for the system volume is critical for removing waste in saltwater tanks.

Durable, Clear Glass or Acrylic

Tanks made from thick, pure glass or optically clear acrylic that won’t easily scratch or cloud. Low iron glass provides unparalleled clarity.

Lifespan of Lighting System

Ensure LED lighting will last several years before needing replacement. Opt for energy efficient fixtures with sunrise/sunset effects.

Adequate Drainage and Plumbing

Bulkheads, ball valves, and PVC pipes should be rated for marine use. Pay attention to plumbing sizes and head height.

Sleek, Professional Design

Aesthetics do matter with these showpiece systems. Seek flawless silicone work, concealed rims, and curved glass for elegance.

Reputable Craftsmanship

Stick with proven brands that use high tolerances and rigorous leak testing. This avoids problems down the road.

Setting Up Your All-In-One Saltwater Aquarium

Once you select the perfect AIO tank, it’s time for the fun part—setting it up! Follow this process for a smooth start:

Assemble the Tank

Carefully unpack all the components and assemble per the manufacturer instructions. Place the tank on a strong, level surface that can bear the substantial weight.

Add the Substrate

Add 2-4 inches of fine marine substrate like crushed coral or aragonite sand. This provides beneficial bacteria habitat and natural aesthetics.

Install Hardware

Insert filtration media like filter socks, foam blocks, and activated carbon as specified by the tank instructions.

Add Live Rock

Arrange cured live rock to create a stable reef structure. This porous rock houses essential bacteria and adds interesting topography.

Fill Slowly with Saltwater

Premix high-quality saltwater starting with RO/DI purified water. Pour water gently into the tank to avoid disturbing substrate.

Power Up Equipment

Plug in pump(s), skimmer, heater and lights. Let the tank cycle for several weeks as bacterial colonies establish.

Introduce Clean Up Crew

Add hearty cleaners like snails, hermit crabs and shrimp to graze algae during the cycle.

Perform Water Changes

Test parameters like ammonia, nitrites, nitrates, pH, calcium, etc. Change 10-20% water weekly.

Add Your Marine Life

Once cycling completes and water parameters are ideal, begin stocking hardy fish/corals. Take it slow and quarantine new additions.

Enjoy Your Slice of the Sea

Finish filling in your aquascape with corals, fish and invertebrates. Now relax and enjoy your thriving underwater world!

Maintaining a Healthy AIO Saltwater Habitat

While simplified, all-in-one tanks still require regular maintenance and monitoring:

  • Test alkalinity, nitrates, phosphates, calcium and other levels weekly. Tweak as needed to maintain ideal ranges.
  • Perform 10-20% water changes weekly using pre-mixed saltwater or RO/DI water plus salt mix.
  • Clean protein skimmer collection cups regularly to ensure efficient waste removal.
  • Rinse mechanical filtration media like filter socks in old tank water monthly to clear debris buildup.
  • Trim and frag fast growing corals to prevent them from overtaking other species.
  • Remove algae buildup from glass manually or with algae scraping magnets.
  • Monitor flow rate and direction. Adjust or add powerheads as needed to prevent dead spots.
  • Inspect plumbing for leaks and clear blocked drain lines causing backup.
  • Calibrate equipment regularly including heaters, pumps, lights and timers.
  • Feed a varied diet including frozen foods like mysis shrimp and quality pellet foods.
  • Introduce new fish, corals and invertebrates slowly and quarantine them first.

While more work than freshwater systems, establishing good maintenance habits will keep your AIO saltwater tank thriving for years.

Troubleshooting Common All-In-One Aquarium Issues

Even well-designed AIO systems can sometimes experience problems. Here are solutions for some potential issues:

Cloudy Water

  • Cause: Bacteria bloom, particulate matter, organic waste buildup
  • Solutions: Use micron filter socks, increase water changes, improve protein skimming, reduce feeding

Excess Algae Growth

  • Cause: Excess light, silicates, phosphates, low flow
  • Solutions: Reduce light duration, add clean up crew (snails, crabs), use a phosphate remover, improve flow/circulation

Coral Decline or Bleaching

  • Cause: Water parameter changes, pests like flatworms, insufficient lighting
  • Solutions: Test and restore calcium, pH, alkalinity, magnesium, and nutrients. Remove pests, adjust lighting.

Equipment Malfunction

  • Cause: Pump failure, heater malfunction, blown LEDs, overflow blockage
  • Solutions: Install new pump, replace heater, swap lighting unit, clear overflow and improve drainage


  • Cause: Defective seals, cracked overflow or plumbing
  • Solutions: Drain tank and reseal leaking areas, replace broken part causing leak

Marine Ich Outbreak

  • Cause: Stressed fish vulnerable to infection
  • Solutions: Quarantine new fish, improve water quality, use copper-safe ich medication as directed

High Nitrate/Phosphate Levels

  • Cause: Overfeeding, overstocking, low water changes
  • Solutions: Adjust feeding, reduce bioload, increase water changes, use chemical media

Pump Noise or Failure

  • Cause: Wear and tear, air bubbles in line, stuck impeller
  • Solutions: Clean out pump, lubricate impeller shaft, replace pump

Catching issues early and troubleshooting quickly helps avoid catastrophic failures. Having contingency plans and backup equipment allows you to resolve common problems swiftly.

FAQs About All-In-One Saltwater Aquariums

Are all-in-one tanks suitable for beginners?

AIO aquariums are great starter tanks due to their simplicity and “plug & play” design. Just be sure to research proper marine care.

What maintenance do AIO tanks require?

Expect to spend 30-60 minutes weekly on water changes, glass cleaning, skimmer cleanup, filter maintenance and testing water parameters.

Can you put coral in an all-in-one aquarium?

Yes, many all-in-one tanks are well-suited for reef builds. Ensure the lighting and flow meet corals’ needs. Start with hardy species first.

What fish can I keep in an all-in-one saltwater tank?

Great starter fish include clownfish, gobies, blennies, chromis, and basslets. Avoid fish needing large swimming areas.

How do you clean an all-in-one aquarium?

Use algae scrapers on glass. Rinse mechanical filtration weekly. Change 10-15% water biweekly. Deep clean pumps every 6 months.

How often should you change water in an AIO tank?

Aim to change 10-15% of the water weekly. Test parameters like nitrate to determine if more frequent changes are needed.

Can you put a sump on an all-in-one tank?

It’s tricky but possible. You must drill the tank and add plumbing to connect to an external sump below. This requires advanced skills.

Do all-in-one tanks need protein skimmers?

Protein skimming is crucial in saltwater tanks to remove dissolved organic waste. Make sure the AIO model includes an efficient skimmer.

Are all-in-one saltwater tanks expensive to run?

The initial investment is reasonable but monthly costs for salt, power, food, and supplies add up. Budget $50-100 per month.

Getting Creative With All-In-One Aquascapes

One of the best parts of the aquarium hobby is aquascaping – creating stunning underwater landscapes in your tank. All-in-one saltwater aquariums provide the perfect canvas for your creative visions. Here are some inspiring aquascaping ideas to make your AIO truly unique:

Mini Reef Wall

Construct a miniature reef cliff in your tank with shelves, overhangs, and caves for corals. Stack live rock strategically, leaving gaps for corals to peer out. Accent with smaller boulders. The height creates depth and complexity. Place vibrant SPS corals on the tops of rock formations and let LPS corals nestle into the cracks and crevices.

Dutch Style Reef

Inspired by lush Dutch aquarium designs, this style uses terraces made from live rock bordered by coral colonies. Build staggered tiers that descend across the tank from back to front. Populate the terraces with contrasting corals like frogspawn next to maxima clams. Let coralline algae grow to cover the rockwork. Use the terracing to control heights.

Seahorse Seascape

For tanks dedicated to housing seahorses, craft a serene garden for them to wrap their tails around. Use branching gorgonians secured to rock piles to create areas for the seahorses to latch onto. Place shorter grasses and macroalgaes across the sandy bed. Build low rock mounds covered in sponges and soft corals. Keep an open sand bed for foraging and limit high flow.

Mixed Coral Reef

The quintessential reef aquascape style combines a diversity of corals into a thriving ecosystem. Start with a foundation of live rock and populate it with a vibrant collection of soft and hard corals. Mix morphologies like large polyp stony corals with leathery mushrooms. Use faster growing corals like xenia to fill in space between showpiece colonies. Scatter shells and urchins across the substrate.

Minimalist Biotope

For a focused ecosystem, create a simple biotope with just a few elements. For example, build a Fijian reef with only native species like fields of pulsing xenia interspersed with small rocky outcroppings. Or construct an Indonesian reef wall with plating montipora corals layered across slab-like structures. Keep livestock choices limited to match the geographic theme.

Underwater Cliff

Inspired by stunning coral walls found on reef slopes, craft a sheer vertical rock face in your tank. Lean large rocks against the back pane and stack additional pieces to build the foundation. Cover it with gorgeously plated stony corals like acropora. Train leatherys and other vines to drape off the overhangs. Populate with anthias and fairy wrasses that use the cliff.

Aquascaping is a chance to unleash your creativity! An all-in-one tank provides the ideal platform to design your dream reef. Let your imagination run wild.

Stocking Livestock for All-In-One Tanks

The perfect mix of fish and invertebrates is key for an all-in-one system. You want active, interesting species that fit comfortably within the smaller footprint. Here are some outstanding livestock choices:

Best Fish

  • Clownfish – These personable favorites come in many colors. A pair makes a great centerpiece.
  • Royal Gramma – Stunning purple and yellow basslets with loads of personality.
  • Cardinalfish – Elegant, peaceful midwater swimmers like Banggai cardinals.
  • Firefish – Darting beauties like the purple or ruby head firefish.
  • Blennies – Entertaining bottom dwellers like lawnmower or scooter blennies.
  • Gobies – Sand sifters like diamond gobies plus shrimp pairings.
  • Wrasses – Small, active wrasses including sixlines and pink streaked.

Favorite Invertebrates

  • Shrimp – Cleaner, peppermint, coral banded add great activity.
  • Snails – Algae grazers like trochus, turbo, nerite, and margarita snails.
  • Sea Urchins – Helpful grazers like pencil urchins.
  • Crabs – Hermit and emerald crabs scavenge debris.
  • Anemones – Stunning bubble tip or rock anemones.
  • Clams – Bright maxima or crocea clams with mesmerizing mantles.
  • Starfish – Cool additions like sand or serpent stars.

Eye Catching Corals

  • Zoanthids – Tough, colorful button polyps that thrive.
  • Leather corals – Flowing branches like Kenya tree or mushroom corals.
  • LPS corals – Hardier large polyp corals like frogspawn or hammer.
  • Soft Corals – Pulsing xenia, neon green star polyps.

Carefully selecting your livestock mix based on behaviors and space limitations is key to a smoothly running all-in-one habitat. Mix active species with those that add movement and color.

Pushing the Limits With High-Tech All-In-One Tanks

For advanced aquarists, upgrading components can transform an AIO tank into a cutting-edge marine habitat. High-tech options include:

Advanced Circulation Systems

  • Controllable pumps like Ecotech Marine Vortechs offer precise flow for delicate corals.
  • Closed loop systems with multiple tunable powerheads improve flow patterns.
  • Specialty wavemakers create pulsing currents that mimic ocean surges.

High-End Filtration

  • Dual skimmers for increased waste removal.
  • Expanded reactor chambers allow use of specialized filter media like biopellets or activated zeolite.
  • Additional mechanical trays fitted with fine micron filter pads for polishing.

Auto Top-Off Units

  • Optical or float switch sensors trigger fresh RO/DI water to replace evaporated water.
  • Maintain stable salinity and prevent nuisance overflow shutdowns.

Automated Dosing Pumps

  • Refill trace elements and critical supplements like calcium, alkalinity, and magnesium on a schedule.
  • Provide optimal, steady nutrient levels for corals and clams.

Controller Systems

  • Centralized units manage lighting, pumps, skimmers and more on programmed routines.
  • Monitor pH, ORP, temperature, and other parameters with electronic probes.

Pushing the boundaries lets advanced AIO tanks rival elaborate custom systems. Why settle for an out-of-the-box experience when you can customize and optimize your all-in-one habitat?


All-in-one aquariums offer a convenient and cost-effective way to dive into the saltwater aquarium hobby. They come in various sizes, from 20 to 50 gallons and beyond, and are generally easy to set up and maintain. However, they may not be suitable for everyone, especially those who wish to expand their setup with additional equipment.