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Setting Up Your Coralife BioCube: A Complete Guide

Setting up your first reef aquarium can be extremely overwhelming. There on tons on tank options, hundreds of different lighting systems, and a wide range of filtration setups. Knowing where to start is often the most confusing part of the hobby.

When helping beginners set up their first reef aquarium, I often tell them to look into All In One tanks. All In One aquariums, as their name suggests, contain everything that a new aquarium owner needs to run a successful reef. This eliminates a lot of  need to chose between hundreds of different lighting, filtration, and tank options.

The best All In One system currently on the market is the Coralife BioCube.

biocube set up guide

The Coralife BioCube

Coralife LED BioCube Aquarium Fish Tank Kit, 32 Gallon
  • Programmable hinge top hood with 24-hour timer...
  • Features 30-minute gradual sunrise/sunset and...
  • Integrate backwall filtration chambers to hold...

The Coralife BioCube is a staple among beginners in the saltwater aquarium hobby. The BioCube first enetered the market years ago, but was recently bought out by Coralife and redesigned into a high quality all in one tank.

The new BioCube has an amazing set of LED light and a built in filtration system in the back. It is available in 16 gallon and 32 gallon models, which are both great sizes for any beginner.

Through our complete guide, you will have a smooth running reef tank in no time!

Step 1: Start Off Right with High-Quality Live Sand

Starting your BioCube off on the right foot is incredibly important. Like everything in life, the decisions you make in the beginning will follow you for a long time.

Using a high quality live sand in your tank will help speed up the cycling process, introduce healthy bacteria, and improve the quality of your water.

I personally recommend CaribSea Arag-Alive Pink Sand when first setting up a saltwater aquarium. I’ve been using this brand for years. It looks great and really helps get the cycling process started. 

Anything by CaribSea is great, but their Arag-Alive Fiji Pink sand is bar-none! It is nicely colored and the grains are perfectly sized.

It is no secret that many reefers have mixed opinions on live sand; some say its not necessary and others swear by it. I have cycled quite a few aquariums, and I definitely notice that the process goes faster when I use CaribSea sand.

Step 2: Load Up On Live Rock

I remember setting up my first reef tank when I was only 15 years old, when the hobby was much different. I told my mother that I needed “live” rock for my fish tank, and she was completely shocked. Lets just say that I got made fun of from my family for a while for thinking rocks could be “living”.

In reality, live rock is one of the most important pieces of a reef tank. Live rock introduces a host of different beneficial bacteria and hitchhikers to your tank. These microscopic critters are crucial to the biological filtration process that takes place in your aquarium. In short, nothing could live in a reef tank without them!

Because live rock is so porous and has tons of tiny living spaces, it provides a great place for beneficial bacteria to live and reproduce. In fact, more beneficial bacteria live on your live rock than filter pads, sand, tank walls, or the water column.

Live rock can get expensive. $10 a pound adds up quite quickly. In many of my tanks, I buy cheap base rock from the local fish store and “seed” it with a small piece of live rock. This base rock is dry and has never been in an aquarium before, so it lacks any of the necessary beneficial bacteria. Placing a good amount of base rock in an aquarium with some small pieces of live rock will allow the beneficial bacteria to spread and populate the base rock. Your dry base rock will be crawling with microscopic critters within a few weeks! This process is slower and delays the cycle, but is much cheaper for those on a budget.

If you’re looking to save some money, I definitely recommend this method.

Recommended Base Rock: Carib Sea South Sea Base Rock
  • No curing needed, South Seas is ready to use right...
  • It makes the best live rock to, takes coralline...
  • Package Dimensions: 18.415 L x 33.528H...

Step 3: Set Up The Back Filter Chambers Correctly

One of the great things about BioCubes is the back filter chamber. Everything you need to run a great filtration system can fit right in the back of the tank!

If you can afford to spend a little extra money, I would highly recommend getting a BioCube 32 Media Basket by inTank. InTank is an amazing company and their products are top of the line.

No matter what you see one the Coralife website, DO NOT put BioBalls inside any of the chambers or media basket.

BioBalls are Nitrate factories and will elevate harmful toxins in your tank. Instead, I like to use a mixuture of Chemipure Elite and Purigen, both of which remove toxins and harmful chemicals from your tank. The remaining back chambers should contain the return pump (included with BioCube) and heaters. For more BioCube add-ons, check out our list of the best Biocube accessories on the market.

Step 4: Wait and Let Your Tank Cycle

After your have added the live sand and live rock to you BioCube, the waiting game begins. Waiting for your tank to cycle can be incredibly annoying. Your new saltwater aquarium looks all sparkly and ready to go, but unfortunately you can add fish just yet. The water in your tank is most likely highly toxic to fish, so you have to wait for Ammonia and Nitrite levels to drop down to normal.

To track the progress of your cycle, you are going to need a good test kit. The API Saltwater Master Test Kit is widely recognized as the most accurate saltwater test kit on the market.

Recommended Product: API Saltwater Master Test Kit
  • Contains one (1) API SALTWATER MASTER TEST KIT...
  • API SALTWATER MASTER TEST KIT helps monitor...
  • API MARINE FLAKES Fish Food includes key nutrients...

Over the course of 2-3 weeks, you will notice a spike and fall of Ammonia, followed by a spike and fall on Nitrite. After Ammonia and Nitrite fall, Nitrate will sharply rise. When Ammonia and Nitrite have fallen to zero, this indicates that Nitrifying bacteria are present and your BioCube is cycled. Make sure to to a large water change before adding any fish. This water change removes the high levels of Nitrate, which is toxin to fish in high amounts.

While this is a very simple explanation of the Nitrogen cycle, it gives you a good idea of how the process works. If you would like a more detailed explanation of the nitrogen cycle and how to speed up the process, you can read about it here. The most important thing to remember is to be patient. Nothing good in this hobby happens fast.

Step 5: Pick Out the Right Livestock


If it is your first time owning a saltwater aquarium, it is best to pick out a few hardy fish. You likely will make some mistakes in the beginning, so having hardy fish will help reduce losses as best as possible.

Some of the best saltwater aquarium fish for beginners are Damsels, Chromis, Wrasses, and Clownfish. Personally, Clownfish are among my favorite and each have unique personalities.

If you plan to keep corals in you new BioCube, I would recommend waiting a few weeks before adding any. Coral is much more sensitive to water conditions than fish and require a more stable tank.

After a few weeks of testing and good results with fish, adding coral is perfectly okay. Start with easy-to-keep soft corals that don’t require pristine conditions. Some beginner corals include Xenia, Green Star Polyps, Kenya Trees, Zoanthids, and Leather Corals.

Step 6: Keep Up with Necessary Maintenance

Water changes are a necessary evil in the world of saltwater fish tanks. On one hand they are inconvenient and relentless; no matter how healthy you tank is, you have to stay on a strict water change regimen. Traveling back and forth to the local fish store will become a habit. On the other hand, water changes replace vital trace elements and remove unwanted toxins.

When it comes to maintenance on your BioCube, you really just have to suck it up and do it. That being said, replacing 20% of the water each week is often unnecessary. As a beginner, you are probably just keeping soft corals and hardy fish. Since nothing in your tank is extremely sensitive to water changes, you can probably get away with a 10-20% water change every 2-3 weeks. In between water changes, simply top off the tank with RO/DI or Distilled water.

If you would prefer to mix your own saltwater instead of going out to the fish store for every water change, we published a list of the best salt mixes for reef tanks. Choosing a good salt mix can not only make the hobby a lot easier, but it can also save you tons of money! Read through out complete guide to for instructions on how to buy and use a great salt mix.

Jason Roberts
About Jason Roberts
Jason is an aquarium fanatic that has been a fish hobbyist for almost three decades.

3 thoughts on “Setting Up Your Coralife BioCube: A Complete Guide”

  1. The Biocube32 lighting Is adequate for low PAR level corals,Coralife claims a PAR level of 60,actually it’s much less, woefully inadequate for sps..if I decide to add sps,acro corals I will have to replace the hood with a screen top and a more powerful led,I have a Red Sea reef 50 on hand..
    For a fish only tank it’s good as is.
    I recommend a Tunze nano skimmer or the IceCap K50..Both fit nicely without the hood.
    Filter chamber 2 can be used as a fefugium with proper lighting and clean algae..get mine from
    Nice looking tank,ideal for beginners,office tank or those just want a marine tank that won’t cost a small fortune.
    Sum it up as a nice mid nano size tank.

  2. ive read many different opinions about stocking, from 1 inch of fish per gallon to 1 inch per 5 gallons….also about tank volume for a fish ie 70 gallons for a dwarf angel (had a dwarf in a 32 gal bio and was fine) are some of these opinions based on amount of maintenance and attention required or maybe just the luck of the draw when stocking

  3. First I’d like to say, this was very informative and I appreciate all the information. The one question I have is, what about the water? Do I buy a mix or do I buy the gallons of salt water? Let me know what you think and how I should go about it.


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