How to Add Sand To Your Marine Aquarium - Tips and Tricks to Get Started

Welcome to Simple Reefs. We have been putting together a lot of articles to help you get started on your marine aquarium ownership journey. Our aim, on Simple Reefs, is to make the process of owning your own piece of the ocean as affordable and easy as possible. In this article, we are going to be showing you how to add sand to your marine aquarium.

We have been talking a lot about sand in marine aquariums, as of late. We go over the pros and cons of a sand bed in this article right here. If you are undecided on whether or not to include sand in your set up, feel free to take a look at that article for a few reasons why you should and a few reasons why you might want to avoid it.

We also go in depth on the differences between live sand and dry sand, as well as helping you decide which to start with in these new articles so click the links to check them out.

In short, there are a lot of benefits to having a sand bed. Not least of which are the opportunities for more biodiversity and a more authentic reef aesthetic. If you have already made your decision, when it comes to adding sand, you are in the right place. As, in this article, we are going to be telling you how to add sand to your marine aquarium. We have a few tips and tricks to make your life easier so let’s take a look.

1. Plan Out Your Aquascape First

This is very important. A lot of people make a big mistake when starting their first marine aquarium. They place their sand in the tank, then they add their rocks on top of the sand. This is a real no go with potential for severe consequences.

You must always place your rocks on the base of the tank. They need to be touching the bottom glass of your aquarium. They should never be on top of the sand. If your rocks are placed on top of the sand. Wavemakers, gyres, fish, and critters, that move the sand around can cause rock slips.

When the rocks slip, they can crush fish, lead to structural collapses and, worst of all, break the glass leading to catastrophic failure of the aquarium. It is not worth the risk. Plan your aquascape, set it up in the aquarium and make sure it is stable before adding your sand.

2. Choose Your Sand Carefully

This is more important than it may initially seem. When planning your tank, carefully pick the type of sand you want to have in your aquarium. Do you want bright white sand? Would you like black sand for something different? Do you plan to have a lot of flow so need thicker grain sand? Would you prefer a denser, broken coral, type of substrate?

These are all really important decisions because it is incredibly frustrating to remove and change sand once you have matured your tank. Removing sand has to be done slowly to avoid upsetting the biodiversity of the aquarium. Removing a lot of sand in one go can risk ammonia spikes, potentially endangering all of your residents. Make sure that the sand you buy is going to be the sand you want to stick with for the long term.

3. Plan The Amount of Sand You Need

Believe it or not, a lot of places will relate hard and fast rules about how much sand you should have in your marine aquarium. The truth is, it comes down to personal preference. You can go bare bottom if you like or just have a dusting of sand. It’s all down to what you find more appealing. There tends to be two types of sand beds when it comes to marine aquariums. They are a Shallow Sand Bed (SSB) and a Deep Sand Bed (DSB).

There are certain benefits that come from certain depths. A shallow sand bed (SSB) tends to have a depth of around an inch or two and offers benefits like better aesthetics and more biodiversity. All while avoiding the complications of pockets of toxic gas accumulating in the sand. A shallow sand bed is easier to maintain and much more affordable, as well.

A Deep Sand Bed (DSB) will usually have a depth of a least 4 inches. A deep sand bed allows for the growth of a specific type of anaerobic bacteria, deep in the sand, which actually consumes nitrates and turns them into nitrogen gas which should, then, release from the water. This, obviously, affords the water greater stability which, in turn, reduces maintenance.

Deep sand beds should be accompanied by a decent number of burrowing creatures like snails to keep it stirred up. Preventing potentially harmful pockets of toxic gas from forming. A deep sand bed is a topic that causes some controversy thanks to its purported benefits and risks. It is also quite expensive and adds a lot of weight to your aquarium. We will be going into this, more, in a future article but, suffice to say, plenty of people see great success with them.

Bulk Reef Supply has a calculator to help you calculate how many pounds, or kilos, of sand you will need for a sand bed of a certain depth based on the size of your aquarium. Plan out and purchase the amount you need beforehand so you aren’t left needing to wait for more to be delivered or settling for less.

4. If Using Dry Sand, Rinse It

If your sand is dry sand, you are going to want to rinse it. What do we mean by dry sand? Well, we mean sand that has no bacteria living in it. Live sand is an entirely different type of product that comes infused with nitrifying bacteria to help start your tank’s cycling process. We talk all about the differences in our article on What Are The Differences Between Live Sand and Dry Sand? Feel free to check that out for more answers.

Live Sand does not need rinsing and, in fact, rinsing it can be detrimental as it may kill off the bacteria present in the sand. Dry Sand, however, comes in a dry bag and is, typically, full of dust and dirt. It needs rinsing before it can be placed in your aquarium. We have a guide on how to do that in our article on How and Why You Should Rinse Dry Sand. Once your sand is rinsed, you can move onto the next step.

5. Make Sure Your Aquarium’s Stand is Stable

This is a very important step that is, often, overlooked. This is doubly important if you are converting an old freshwater aquarium and stand into a marine aquarium. With your aquarium filled with rocks, you want to make sure that your stand is stable. You are about to add a bunch of extra weight to the aquarium with the addition of sand and water.

Sand can easily take up as much weight as the rocks in your aquarium. My 4x2x2ft Red Sea Reefer aquarium has at least 40KGs of sand in it. My Fluval 52l has over 9KG as it is a deep sand bed specifically designed to house a pistol shrimp. That’s a lot of weight and freshwater stands, in particular, are designed to take less weight than marine aquarium stands which are built with the expectation of rocks and sand.

Give everything a gentle move back to front and, more importantly, side to side. Make sure nothing shifts around or you don’t hear any worrying creaking. The side to side movement is what tends to kill aquarium stands so pay special attention to that. All it takes is a slightly wobbly stand being bumped into to end up with litres of water all over the floor. Someone will, almost certainly, bump into it at some point in the future. A stand collapse would be catastrophic to your aquarium so this extra step is important.

6. Place The Sand in the Aquarium

You have two options here. You can either put the sand in first or the water in first. It is totally up to you. I would say that it is easier to put the sand in first and it tends to be less messy, as well, resulting in less clouding up of the water.

Sand Before The Water

Most people, myself included, tend to place the sand into the aquarium first. That way you can distribute it neatly around the bases of the rocks, into any caves, and make sure it is nice and even.

You are then going to want to take either the bag the sand came in, a plastic bag from the kitchen, or a dinner plate, and place it onto the sand. We then pour our water directly onto this bag or plate, slowly. This will avoid the cascading water upsetting the sand and ruining our nicely laid out sand bed.

Fill the tank up to the top. Remove the bag or plate, make any final adjustments to your sand bed and you are done. If you are using live sand that came with a bottle of bacteria or a water clarifying liquid to add, do that now. Turn on your filters, but don’t turn on your gyres or wavemakers, give it 24 hours for everything to settle and clear up, and your aquarium is ready.

Water Before The Sand

If you enjoy a challenge, you can put the water into your aquarium first and then add the sand. It’s as straightforward as filling up your aquarium. Leaving the water level a fair bit short of the top as we are about to add a lot of weight to the tank which will displace the water.

We then add our sand. Rinsed if it is dry sand and unrinsed if it is live sand. Try and spread it liberally around the entire tank, making sure sand reaches the bottom of the rocks and spreads around the entirety of the bottom of the tank. A jug or cup can be very useful for this. Take a jug or cup full, place it where you want it, rinse and repeat.

You will then, almost definitely, be dealing with some fairly cloudy water. Even if you rinsed the sand, some of it will remain suspended in the water column. If you are using live sand, add your water clarifying liquid sachet to the water or the included bottled bacteria. Turn on your filters, but don’t turn on your gyres or wavemakers, and wait 24 hours.

When the water is thoroughly clear. You can now use a wooden spoon or sand shifting tool to redistribute the sand to where you want it. Make sure it is even and there is sand in all of your various caves and crevices. You can then top up your aquarium to the fill level and you are ready to go.

7. Make Final Adjustments

You may find this step to be an ongoing battle for the life of your aquarium ownership. Now that you have your sand in your aquarium. You are going to want to turn on any wavemakers, powerheads, or gyres that you have.

I suggest doing this step after the water has cleared up because doing it while the water is cloudy can mean you have an obstructed view. Your gyres or wavemakers might be kicking sand up in ways you can’t see due to the cloudy water. Meaning the water will take much longer to clear up.

Now that your water is clear, we can see exactly what mess they are making. Turn on your gyres, wavemakers, or powerheads, and watch how they move the sand around. You now want to adjust the position, speed, and direction of said wavemakers to ensure they aren’t creating bald spots on the bottom of the tank. Bald spots look awful and they will grow algae in the same way your glass will.

Sand blowing around can cover up your coral, as well. I have, unfortunately, almost lost coral before due to this happening. This may take a few hours to get right. Repositioning and adjusting until you find the sweet spot. It would be ideal if you could position your flow to keep detritus off the top layer of the sand without blowing the actual sand around. This is very difficult to achieve, though.

It’s worth mentioning that fine grain sand will be much more prone to blowing around and you may end up having to lower your flow levels dramatically to accommodate. Heavier grains of sand are much better for this.

Enjoy Your Reef !

Congratulations, you are done. How cool does that tank look with all the rocks and sand? Growing up with freshwater aquariums. The first time I converted a freshwater tank into a marine aquarium, my mind was blown by how fantastic it looked. Especially compared to boring planted freshwater tanks with driftwood and gravel.

Even with a bright white rock scape and a cheap blue backdrop, it still looked so impressive to me. These first moments admiring your virgin reef are some of the most important in the entire time you will be owning a marine aquarium.

Remember how it feels because that will get you through the ugly stages coming up and some of the difficult times that all marine aquarium owners experience somewhere down the road. It will also help when that first electricity bill comes floating through the door. Your own slice of the ocean is just getting started and the best is yet to come!