Now that you have all the supplies that you need to set up your saltwater fish tank where do you begin to set it up?  In this article we will go over in a step by step format of how to set up your aquarium.  This will be a general guideline and you may need to adjust or add to the steps depending on the equipment you purchased for your set up.  For example a person who purchased a wet/dry filter or sump will set up the tank slightly different than a person who purchased a canister filter for their tank.  With that being said, let us begin the process of setting up your marine aquarium.

Location, Location and Location

First and foremost you will need to find where you are going to put the tank.  Once filled with water, moving the tank will be next to impossible, so make sure you are positive of the location of the tank.  There are a few considerations when finding a spot for the tank.  First the tank should not be located in a place where it will receive direct sunlight.  Direct sunlight on the tank can cause excessive algae growth and/or possible over heating of the water.  A second consideration is putting the tank in a location that is easy for viewing.  If possible put the tank in a room that people spend a majority of their time in.

Make sure the tank is level

Once a tank location has been found, it is now time to put the tank and stand in place.  Make sure the tank is not located too close to the wall as you may need to reach behind the tank to pick up fallen items and you will need to leave room for any equipment that will hang off the back.  First you will want to put the stand in place and make sure it is sitting level.  If the stand is not level, you can use shims to level the stand.

Once the stand is level you can then put your tank in place.  It should be noted that some people will put a piece of Styrofoam or rubber matting between the tank and the stand.  This is to help make sure that any imperfection in the stand will be evened out by the weight of the tank pushing down on the Styrofoam or mat.  Once the tank is in place, double check it again to make sure everything is level and again shim if needed.

The Dry Run

Now that the tank is in place and is level it is time to do a dry run.  A dry run consists of setting up the equipment you have purchased without having water in the tank or plugging in the equipment.  This will allow you to make sure everything you have bought is going to fit into place and will give you an idea of how they will fit.  Also if anything doesn’t fit quite right, you will be able to return the item and exchange it for one that will fit better.  This can especially come in handy when using a wet/dry filter or sump that will sit underneath the main tank.  You will be able to check to make sure the filter fits properly under the tank and has room for you to do any maintenance in the filter.  This will also give you the perfect opportunity to cut the tubing to the correct lengths on canister filters if they are going to be used.

Wet/Dry Filter or Sump Plumbing

If you are not using a wet/dry filter or sump that will require extra plumbing, you can skip to step 6.  If you are using a wet/dry filter or sump now is the time to start plumbing it in.  Most people will use PVC piping, vinyl tubing or a combination of both when hooking up their system.  Ultimately the choice is up to you as to what will work best for your tank.  When you are ready to start do not forget to use Teflon tape on all threaded fittings, PVC glue on any PCV slip connections and hose clamps on fittings where vinyl tubing fits over hose barb fittings.

Tip: If you are using an external pump consider installing a ball valve and a union on both the input and output of the pump.  The correct installation order of the ball valves and unions will be: Ball valve, union, intake to pump, pump, output of pump, union and ball valve when following the water flow going from the wet/dry filter or sump back to the tank.  This will allow you to easily remove the pump for maintenance without having to take the whole plumbing system apart.  There are also union ball valves available for even easier plumbing.

The Wet Run

Once all the connections have been glued or threaded in and clamps have been installed on all vinyl tubing connections it is time to run a wet test to check for leaks.  The wet test is simply filling the tank with water (no need to use filtered water for this) and plug in your return pump.  Check all the fittings for leaks and make sure the pump is not too powerful for your tank.  At this time you can also check the overall flow you will be getting from the return pump through out the tank.

If there are any problems, now is the time to address them.  Some may be a simple fix such as tightening a threaded fitting to stop a leak to adding a ball valve to the output of your return pump to slow down the flow if it is too powerful.  Once you are certain there are no leaks and the return pump is good, you can drain the test water from the tank.

Filling the tank

It is now time to start filling the tank.  There are a few methods to this that we will discuss.  The first method is to simply fill your tank with water with nothing in tank (decoration, sand, etc.).  Fill the tank to the point where you can start to run your filter, pumps/powerheads and heater(s).  Once all the equipment is hooked up you can start turning on the pumps and powerheads to start circulating the water in the tank.  Once the water is circulating in the tank you can start to add the correct amount of synthetic sea salt directly in the water to allow it to start dissolving.  Next as long as your heater(s) have been in the tank for at least 30 minutes, you can now plug it in and start adjusting the temperature of the tank to between 76 to 80 degrees Fahrenheit.  After all the salt has dissolved in the tank you will want to check the specific gravity with your hydrometer or refractometer.  If the specific gravity is low, you will want to add more salt and if it is high you will want to add more freshwater.  Once the specific gravity is within the range of 1.020 to 1.025 you are ready to proceed to the next step.

The second option for filling the tank is to premix the freshwater and synthetic sea salt in a container outside the tank.  This will allow you to measure the salt levels of the water in the containers and adjust each batch as needed.  Once the water is to the correct specific gravity it can then be added to the tank.  With this method you could add your sand and decorations (that will be discussed in the next step) to the tank before you start transferring the water into the tank.  If you do decide to use this method and put your sand and decorations in before you transfer over the saltwater you will want to rinse them before putting them in the tank.

Tip:  It is recommended to use filtered water, such as reverse osmosis, reverse osmosis/deionization water, to help reduce and contaminants found in tap water such as nitrates and phosphates.  At a bare minimum you will want to use a water conditioner to rid your tap water of chlorine, chloramines and to detoxify heavy metals.

The Equipment is Running

At this point your tank should be filled with saltwater at a bare minimum.  If you have not hooked up your pumps and filters yet, now is the time to do this.  All the equipment that was put in the tank for the dry run and wet run should now be hooked up and running on the tank.  Also if you have not set the temperature of the tank with your heater(s) this should also be done now.

Tip: After putting your heater in place, let it sit for at least 30 minutes to allow the unit to get to the same temperature as the tank water.  Once it has been in the tank for this time, you can then plug it in and set the temperature.


It is now time to start decorating, or as aquarist call it aquascaping of your aquarium.  If you have not added you sand yet, this will be the first step to take.  Make sure you rinse the sand before putting it in the aquarium because it is very dusty.  Even after rinsing the sand it will still cause a sand storm in the tank.  Once the sand storm has cleared up some, you can start adding your decorations to the tank.  There is no wrong way to aquascape the tank, but you will want to make sure the rockwork is stable and will not fall over and that you do not block the flow from your water pump return or your powerheads.

Tip: If using liverock, it is best to make sure the rock is fully cured  before adding it to the tank.  This will help prevent fouling of the tank water and minimize the amount of detritus that may accumulate from the curing of the rock.


At this point you should have a fully functioning saltwater aquarium up and running without out any fish yet.  You will wan to let your tank run this way for a week or two.  This may be one of the hardest points in the set up process as you will be looking at an empty tank for a little while.  But your patience will pay off in the long run.

Starting the cycle (or continuing it)

Before discussing how to cycle your tank, first we will quickly discuss what the term “cycling” is referring to in your tank.  Cycling is referring to bacteria breaking down the waste produced (harmful ammonia) by the organisms in your tank to a less harmful compound called nitrate.  This is also referred to as the nitrogen cycle.  Fish will excrete ammonia which is deadly at high levels to your tanks inhabitants.  Naturally in the tank bacteria will form to break down the ammonia into nitrite.  Like ammonia, nitrite is also toxic to your tanks inhabitants.  Another bacterium will form to break down the nitrite in to the less harmful nitrate.  Nitrates can be kept under control in the tank by doing partial water changes to reduce their levels.

Now that you have been staring at an empty tank for the last few weeks, it is time to start the cycling of the tank.  If you used liverock in the tank you have already started the cycling of the tank, but for everyone else a source of ammonia (waste product of fish and inverts) will be needed to start the cycling.  There are a couple of different ways to start the cycling process that we will discuss.  The first way is to put in a few (the number will depend on tank size) hardy fish into the tank.  One of the more popular choices are the damselfish or clownfish.  Once the fish are put in the tank and are being fed, they will start producing ammonia.  Once ammonia is present in the water a beneficial bacteria will start to form to breakdown the ammonia.  The ammonia is broken down into nitrites and another beneficial bacterium will form to break the nitrites down into a less harmful compound called nitrate.  It will usually take 3-8 weeks for a tank to complete this cycle.  During this time the ammonia and nitrites will rise to very high levels that can be toxic to fish.  For this reason many people feel fish should not be used to cycle a tank.  The high levels or ammonia and nitrites can cause permanent damage to the fish or even death.

There are a few better alternatives to help the cycling of your tank.  The first option is to put some cocktail shrimp in your tank.  You can pick up the shrimp from your local grocery store.  As the shrimp breakdown in the tank the same beneficial bacteria will form in the tank and will seed your biological filter media.  A second option is to add some livesand to your sand bed that is already in the tank (or even use all livesand in the tank).  Livesand will already have beneficial bacteria coating the grains of sand and will again help seed your biological media.  One other alternative is to add a small amount of liverock to the tank to help seed the biological filter media.  Once the tank has cycled the liverock can be removed.

Done Cycling, time to start adding fish

No matter how you decide to cycle your tank it is very important to be testing at least once per week during the cycling process.  You will want to test the levels ammonia, nitrite and nitrates in the water along with the pH of the water.  Once you see the ammonia and nitrite levels have dropped to zero, your nitrate levels are below 10-20 ppm and your pH is between 8.0 and 8.6 it should be safe to start adding fish to your tank.  Do not rush out and buy a ton of fish and stock the tank to the maximum level right after the cycle.  You will want to slowly add fish to the tank.  Every time you add a new fish to the tank, the bacteria that breakdown the waste products must increase in population to handle the additional waste being produced.  This takes some time to occur and if too many fish are added at once, the ammonia and/or nitrite levels can rise to harmful levels again.

Keeping up with the maintenance

Hopefully at this point you will have a tank running with a few of your favorite saltwater fish swimming around in it.  From this point on you will be switching from setting up a tank to maintaining a tank.  You will want to continue testing your water (anywhere from once a week to once every other week), doing water changes in the tank and scrubbing algae inside the tank.  With a little work every week, the tank and its inhabitants will continue to thrive and grow.


As mentioned earlier every tank will be set up slightly different, so you may need to adjust these step-by-step recommendations to fit your tanks needs.  But as long as you take your time, add your fish slowly and keep up with the normal maintenance of the tank you will have a beautiful, healthy tank for you to enjoy.