How To Start A Saltwater Aquarium

Dream Saltwater Aquarium

Saltwater aquariums have fascinated and inspired people for decades. There is just something monumental about having a living piece of aquatic art in our homes.

Whether it's the brilliantly colored fish, the mesmerizing coral, incredible biodiversity, sense of satisfaction, or just a simple curiosity for the natural world ...something magnificent draws us in. No matter the reason you find yourself ready to learn about saltwater tanks, let us help you take the first steps.

Bulk Reef Supply is the most trusted authority for saltwater aquarium advice because we are committed to your success. For those of you just starting out, our promise to help you be the best hobbyists you can be starts here.

Step #1 - Imagine Your Dream Tank

Lack of proper planning is the most common reason new saltwater aquarium hobbyists fail. Coming up with clear answers to these simple questions is all you need to do in order to properly plan for your first saltwater tank.

  • What kind of budget do you have?
  • Where will the tank go?
  • How big will it be?
  • What will you keep inside the tank?

Write these answers down and discuss them with your family. Ultimately, these are the most important deciding factors for ending up with a tank that you will be happy with, long term.


5 Minute Saltwater Aquarium Guide

Watch and learn how to setup and maintain your very own saltwater aquarium

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Step #2 - Choose Your Tank

Buying the right tank doesn’t have to be difficult. You already laid out the most important factors in choosing a tank in Step #1 and now it’s just a matter of finding a tank that suits your needs.

Generally speaking, there are three different types of tanks based upon their life support or filtration system.

  • All-In-One or AIO: An aquarium with filtration built right into the back of the display.
  • Sump: Filtration that is housed remotely from the display, typically down below inside the tank stand.
  • Hang-On: Filtration equipment is either hung on the side of the tank or submersed directly into the display.

Our best advice for first time tank owners is to choose a tank package that, at very minimum, includes the filtration. All-In-One tanks or complete packages with a sump are always going to be the easiest route because it eliminates the need for you to choose and build your basic life support.

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Step #3 Filtration, Water Flow, and Lighting

After you have chosen your tank, the next step is to acquire any additional equipment. Every tank is different so this will be very specific to your particular tank and desired livestock.

Water filtration in general has three stages; mechanical, biological, and chemical filtration. The way these concepts are applied will vary widely but ALL successful aquarium filters will accommodate these three stages of filtration in some way or another.

Mechanical Filtration

This is where particles and sediments are physically removed from the water. Filter pads, filter socks, plastic sponges and even protein skimmers are all mechanical filters.

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Biological Filtration

Technically speaking, naturally occurring beneficial bacteria is what makes up your biological filter. As hobbyists, we simply provide sand, rocks, and biological filter media as the ideal substrate for this beneficial bacteria to grow.

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Chemical Filtration

Media or additives designed to change the chemical composition of the water. Used most often to target and remove dissolved impurities that cannot be physically removed via other methods.

Activated carbon, granular ferric oxide and specialty filter resins like Chemi-Pure are all very common examples of chemical filtration in a saltwater aquarium.

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Water Flow

Media or additives designed to change the chemical composition of the water. Used most often to target and remove dissolved impurities that cannot be physically removed via other methods.

Activated carbon, granular ferric oxide and specialty filter resins like Chemi-Pure are all very common examples of chemical filtration in a saltwater aquarium.

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Most saltwater aquariums are going to require lighting and LED lighting is the preferred technology for modern aquariums for a number of reasons. It is efficient, easy to use and does not require upkeep or maintenance.

Pro Tip: Contact our Customer Service Team for friendly advice. Our team of knowledgeable hobbyists will provide live 1 on 1 support and help you through the buying process or simply talk tank anytime!

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Step #4 Rock, Sand, and Water - Aquascape


Saltwater aquariums rely on porous calcium carbonate based rock to maintain a stable biological filter and provide the primary habitat for the fish and corals to live.

You can buy pre-assembled rock structures, often called aquascapes, or build your own using a variety of different styles, shapes, sizes and colors.

There are man-made rocks like Real Reef or Caribsea LifeRock or naturally harvested rock such as Marco Rocks and ocean live rock from your local fish store. Regardless of which you choose, appearance is important so choose rock that looks good to you.

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Sand is completely optional but 99% of saltwater hobbyists choose to use it. Not only does it add to the overall natural aesthetic, sand provides an incredible amount of surface area for beneficial bacteria to colonize.

Choose sand based on appearance, it all works the same. We generally only recommend a 1” - 2” sand bed, anything deeper becomes difficult to keep clean. You can use the sand bed calculator to easily find out how much you need.

Pro Tip: Live sand is worth the extra expense. You won’t have to hassle with rinsing the sand like you will with dry sand and the beneficial bacteria will help cycle your aquarium faster.

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Saltwater aquariums require freshwater purified with an RO/DI system to replace water that evaporates on a daily basis and to mix saltwater used for water changes.

RO/DI systems are easy to hook-up and can be connected to your faucet, garden hose, or directly to a water line and will provide you with purified RO/DI water on demand.

Mixing seawater at home is easy once you have an RO/DI system. It will also save you a ton of time and money compared to purchasing saltwater from your local fish store.

Pro Tip: When choosing a salt mix brand, pick one and stick with it. Success can be had with any of the brands we carry and the most important factor is stability.

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RO/DI Buyers Guide

Watch and learn how to select the right RO/DI System for your reef tank in 10 Minutes

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Step #5 - Setup And Cycle

At last the fun begins, the time has come to put all of the aquarium equipment you learned about together and begin to prepare your aquarium for your first fish.

  1. Prepare your water. You want to have enough fully mixed saltwater on hand to fill your tank.
  2. Assemble your tank and stand. Place it in its final location. Once the tank is filled with water, it will be too heavy to move it. Be sure the tank is level.
  3. Install additional equipment but do apply power! Focus on routing the power cords neatly, label them, and avoiding hazardous nests of wires.
  4. Build your aquascape.
  5. Add sand after the aquascape which helps stabilize the rocks.
  6. Carefully fill the aquarium with saltwater, if the water is cloudy let it settle for a few minutes and remove any debris.
  7. Turn on the main return pump first, observe for proper flow and function.
  8. Proceed to power on the remaining equipment one by one.

After the basic setup and filling with water, your aquarium needs to cycle before adding any fish or livestock. This is when your biological filter is being established which typically takes 2-4 weeks.

Bacteria additives such as Brightwell Aquatics MicroBacter 7 can help introduce various bacteria strains into your tank and help quicken the cycle process.

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Step #6 - Setup And Cycle

Of course, adding fish and other livestock is your last step and perhaps the most exciting part of the process. Take the time during your cycle to further plan and research the animals you want to keep.

Remember, nothing good happens fast with an aquarium, especially when it comes to stocking the tank. A good general rule to follow is no more than 2 fish at one time and always at least 2 weeks in between additions. This ensures you're not adding too many fish at one time and allows your tank to stabilize in between additions.

Find A Fish Store

Having a trusted local fish store for livestock, insight and support will be invaluable. You want to establish a relationship with one or more of the employees so they can get to know you and your tank. Shake hands, exchange names and visit often to display loyalty.

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Meet a Mentor

We often advise new hobbyists to “Listen to somebody, not everybody.” This simply means choose a mentor who you look up to and follow only their advice. Replicating an already proven path is far easier then paving your own.