Aquarium Substrate Calculator

One challenge in planning for a new planted aquarium is determining how much substrate you need for your planted aquarium.  It becomes challenging to compare various brands of substrate (that all come packaged with different volumes of product in each bag) and plan for the number of bags that your setup will require and budget for the resulting cost.

To help with this, I have created an Aquarium Substrate Calculator.  You can enter the dimensions of your aquarium and the desired depth of substrate, and it will calculate the volume of substrate you will need.  I have made things uniform by making all volume calculations in Liters.  One thing to note is the first user input to select a preference for inches or centimeters.

Select from the list of substrates and it will tell you how many bags you need to purchase and the estimated total cost (in US dollars).  You can modify the fields for ‘Liters per Bag’ and ‘Cost per Bag’ after they are populated if you have an updated price or product.  The costs are based on the current price on Amazon (shipping costs are not included).

up aqua aqua sand substrate 2" depth

Concerning the desired depth, it can vary from 1 to 4 inches (2.5 to 10 cm) depending on the scale of the aquarium and the needs of the plants.  If you are planning on a large slope of substrate, you will have to visualize where the midpoint of this slope will be and make that point an estimated depth.  I have an average depth of around 2.5 inches (6.4 cm) in our Fluval Spec V Aquarium.

The values for volume per bag and cost per bag in this substrate calculator are based on my research and, in the case of Up Aqua Aquasand, from a bag that I purchased for our tank.  Below the calculator I have more information on the substrates I have included in this calculator.  Cost can vary greatly, especially when considering shipping for multiple bags of substrate.  Feel free to check on the cost for the number of bags and update the fields for a more accurate total.

  • ADA Aqua Soil Amazonia – This has long been the standard for planted aquariums.  It comes advertised by volume, in this case it contains 9 Liters of substrate in each bag. It is also available in a 3 Liter bag.  The positives of Amazonia are very nutrient rich and subsequent very good plant growth.   The negatives are that it is so nutrient rich it can cause the ammonia to spike for the first month or so; this may require frequent water changes to keep ammonia levels at a safe level.   The other common disadvantage is that it turns to ‘mud’ or breaks down over time.
  • ADA Aqua Soil Amazonia II – Very similar to Amazonia, but with a few changes to make it more beginner friendly.  ADA is a little fuzzy on the details, but I take it the substrate has fewer nutrients and does not have as big a problem with ammonia leaching at the start.
  • ADA Aqua Soil Amazonia Light – Same characteristics as the Amazonia II (less issues with ammonia at start) and in a lighter hue (more brown than black).
  • Up Aqua AquaSand – This is the substrate that I chose for the recent rescape of our aquarium. It is sold in 5 kg bags. I measured the volume as 4.4 liters.  I have a review here.
  • Seachem Flourite Black – This substate is what I initially had in our nano aquarium.  It is sold in a 7 kg bag.  The Seachem webiste puts this bag at 5.3 Liters.
  • Fluval Plant and Shrimp Stratum – I have not used this but it gets good reviews for planted tank enthusiast.  It comes in 4.4 lb and 8.8 lb bags.  I estimate that the 8.8 lb bags have a volume of around 5.4 Liters.
  • CaribSea Eco-Complete – This is similar to fluorite.  It is sold in a 20 lb (9.1 kg) bag.  Eco Complete is sold with some water already in it that supposedly helps to cycle your aquarium.  This water throws off the conversion from mass to volume a bit, but I estimate each bag has 5.9 Liters.

The good news for people setting up a Spec Aquarium, whether it is the smaller III or the larger V, one bag of whatever substrate you choose will probably be enough.

16 thoughts on “Aquarium Substrate Calculator

  1. Nice articles and valuable stuff to provide to all fish lover like myself 😛
    Thanks for all the information!

  2. Thanks very helpful ,i have a 48″x20″ aquarium and want to plant up ,im not sure of the best substrate to use for the planting to be as good as hope it will be.There seems to be so much advice im not sure who to turn to!!
    I Live in Brighton on the South Coast of England and have to travel far and wide for fish, good plants and looks like substrate from Amazon and good advice from the USA.
    thank you for your help ,and wish me luck.x

    1. Best of luck to ya! I wish I could offer better advice for products over the pond.

  3. I had a lot of trouble figuring out if my substrate choice would fill the bottom of my Fluval Spec III. I used your calculator and I still wasn’t one hundred percent positive. So just to put anyone’s mind at ease who might be wondering, a five pound bag of the popular Caribsea Super Naturals Tahitian Moon Sand will fill a Spec III nicely. Mine has a nice slope of 1.5 inches in the front to just over two in the back. I worried I might have ordered too little and then found a tank set up video on YouTube where the guy used only about 3 pounds of a different Super Naturals and his fill was really deep so I thought yeah I’m safe. When the sand came in I was surprised because it too every bit of it, but it was just right.

  4. Thank you for putting together this wonderful resource Nate. It’s so helpful, and so fun to watch your own experiments and tank exploits. Thanks so much for sharing with us all.

  5. So glad I found this. It’s super handy you have pre selected substrates , also like how you help calulte number of bags and added cost calculator(with simple user edits) Using it to to help figure how much I’ll need for my 72×18. Thanks slot.

    1. Great – glad it’s useful. Good luck on the project – sounds exciting!

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