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How Much Sand for a 20-Gallon Tank?

How Much Sand for a 20-Gallon Tank

How much sand you put in your 20-gallon tank is pretty straightforward, unless you are using your aquarium for crabs. Crabs need a lot more sand in their substrate than fish do. It may vary as well, according to the type of sand that you choose to go with. 

For any standard aquarium fish tank, you want two inches of sand sitting at the bottom. There is an easy way to figure this out. Multiply the length and the width of your 20-gallon tank. Divide the resulting number by 10 and the result is the number of pounds of sand you need for a 2” depth. 

For instance, let’s say your tank is 15” wide and 50” long. Multiply 15 and 50 to get 750. Divide 750 by 10 to get 75lbs. You’ll need 75lbs of sand to get 2” of depth at the bottom of your aquarium. Of course, some sands are lighter than others, so you should be careful when choosing something exotic.

Is Black Sand Good for an Aquarium?

Black sand is generally pretty coarse. It’s not necessarily bad for your tank so much as it may be bad for certain fish. While the coarseness of it is beneficial for fish that like to burrow down into the sand, it’s not good for something like a Cory Cat, a fish that is notorious for choking on certain types of sand. 

It’s really just a matter of doing your homework on what fish prefer in terms of their substrate. You shouldn’t put the fish in front of the sand when you make your choice. You should choose the sand and then pick the fish you want to flourish in this habitat based on the black sand substrate.

Plants aren’t great with sand either, at least not real plants. When it comes to sand substrates, it’s best to go with fake plants to fill up your aquarium with some vibrancy and color. 

What Type of Sand Should I Use?

You should base your sand choice based on the fish that you want to get. The choice in the sand comes from what’s going to be best for the fish. Different types of sand aren’t just concerning for what fish might not be able to pass the grains through their gills but also how it might change the pH in the tank. 

When it comes to different colors of sand, there really isn’t a bad option and a good option. The only option is getting the best sand based on what kind of fish you want to populate your aquarium with. 

The Eco-Complete sands are great because they are clean and boost the pH levels in your tank, which is great if the fish you want prefer higher pH levels. Eco-Complete substrates are also good for getting the cycling process going and it resists pH level drops in the tank as well. 

If you are looking into getting some fish that only tolerate lower pH levels, some of the Eco-Complete options may not be the best idea. 

Which Color Sand is Best for an Aquarium?

Colored sand is perfectly safe and it’s not a matter of what sand is best for an aquarium. If the aquarium is completely empty and we’re answering this question in a bubble, none of the sands out there make a bit of difference. They don’t poison the water or turn the water into some sort of death trap.

They’ll generally improve the conditions in the water and that’s great, for certain types of fish and not so great for others. If you have certain fish that can’t tolerate sand, then no sand you put in your aquarium is going to be good sand. 

How Much Sand in a 10-Gallon Tank?

For the most part, a 10-gallon tank is going to take 19.5lbs to reach the goal of having a 2” substrate. You can always measure the tank, using the above formula, and get an idea of how much you want to add. 

Small tanks are a lot more susceptible to rapid changes in environmental conditions than larger tanks because the volume of water is so low that it doesn’t take long for something to diffuse throughout. 

Some of the best fish for a 10-gallon tank are Betta, Guppies, White Cloud Minnow, Neon Tetras, and Zebra Danio. 

How Much Sand in a 30-Gallon Tank?

Generally speaking, it should take about 64lbs of sand to get your 2” depth in a 30-gallon tank. Depending on the exact shape of the tank, it may change by small degrees by that’s going to be pretty close at the end of the day. 

A 30-gallon tank is one of the easier tanks to manage, 20% water changes periodically and you can stock them with plenty of beautiful fish, such as classic goldfish, killifish, angelfish, molly fish, cory cats, guppies, and rainbow fish.

How Much Sand in a 40-Gallon Tank?

The way that 40-gallon tanks are usually shaped, with increased height, the amount of sand in a 40-gallon tank is often less than what you would need in a 30-gallon tank. For the most part, you will need close to 60lbs of sand to get 2” of depth in a 40-gallon tank. 

Most of the fish you can put in a 30-gallon tank are also the same fish you can put in a 40-gallon tank. Some fish will prefer the larger environment, such as the convict cichlid, three-spot gourami, and cardinal fish.

You can also stock it with mollies, goldfish, betta, cory cats, zebrafish, and more. 40-gallon tanks are getting into the big leagues and you have a lot more options in terms of fish, substrates, plants, and other aesthetic choices for your tank. 

All Things Considered

The amount of sand that goes into your tank is almost entirely predicated on the dimensions of your tank, excluding the height. After that, it’s just a matter of what kind of sand you want to use and what the best fish are for that particular substrate.  

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