Choosing a Substrate for Growing Live Aquarium Plants

If you want to grow live plants in your fish tank or aquarium one of the most important factors in growing plants that will survive is choosing the right substrate.

Substrate is a fancy word for the rocks, gravel, sand, soil or a combination of all of them at the bottom of your tank. For most live plants you will need a substrate for them to hold their roots in and be fixed to the bottom of the tank. However for me, the right substrate will give them the proper nutrients and ability to have a long healthy life.

Aquarium Gravel 

 

The most common substrate that we use is gravel. You can buy aquarium gravel at any pet store or department store. Many live plants will grow in this gravel but very slowly and not with the desired size or color. Plus you will need to continually add fertilizer and supplements.

Aquarium gravel is also often treated with dyes and chemicals that are likely to be damaging to your fish and plants. This is most common with quartz gravel. If you do choose quartz gravel you will need to supplement with laterite or Fluval Substrate. Pea gravel is a much better choice and generally considered more natural looking. It is a great match on top of white sand and mixed in with it.

Aquarium Sand 

 

Sand can be a great alternative to gravel and is an ideal substrate to many available in stores. You will have to be careful though to not get play sand or construction sand. Getting the right sand should be available in the aisle with gravel.  The best sand is available online where you can choose the color and size you need.

If you do use sand it can get very compact and cause sinking. Many aquarium owners complain of it eventually turning to mud.When it sinks, the larger substrate will eventually move to the bottom of the tank and the sand will appear at top, potentially ruining your display.

Natural White Sand is preferred and really cheap

Aquarium Soil aka Aqua Soil

 

Aqua soil is a much better alternative to growing aquarium plants than rock, gravel or sand. However you must be careful with what you choose and be ready to pay for it. Most aqua soils are only available at specialty pet stores. Most pets stores like Pet Pro, Petco, Pet Supplies Plus will not have it.  Amazon is the best option for buying aqua soil. It is rather affordable now, gives several options and is usually under free shipping.

Aquarium soil is best used by it self. Many manufactures, most notably Fluval will tell you explicitly on the directions to not mix the soil with any other substrate. This has angered many people but it is because the light construction of the Fluval substrate will be crushed by anything rock based.

Flourite is one of the best rated options.

Plants that Require Gravel, Stone or Sand

Some of the easier and less demanding plants like the Sea Onion, Vallis or Vava Fern will be just fine with gravel or sand.  They do not require nutrients as much as other aquarium plants but do require something strong and hardy for their roots to be positioned. If you used high end substrates and soils it will be difficult for them to hold their roots and they may float to the top of the tank. You can fill your tank with lots of these because they are light and thin.

Plants that Require a Mix of Stones and Soil

Plants that are quickly growing, branching and sending off shoots are going to require something to hold their roots but also something to give them nutrients for their constant growth. Examples might include Anubias barteri, Orchid Lily, Brazilian Pennywort. These plants will be aggressive and take over your tank. One of each will be enough.

Plants that Require Aqua Soil

The most difficult to grow plants will include those that require constant nutrients. Instead of continually supplementing them with fertilizer tabs and liquids you could use an aqua soil and a CO2 attachment. These plants will include Hairgrass, Dwarf Helzine, and Echinodorus 'Red Special.' These plants will usually require a stronger light too.

Plants that Require No Soil, Gravel or Anything

There are a number of aquatic plants that actually need no substrate to live in your aquarium! One class of plants that will grow perfectly without substrate are those that float at the top. Their nutrients are gathered from the water and bacteria left from fish waste. Some of these plants include the Salvinia's, Water Lettuce and Crystalwort.

Another class of plants that need no soil or substrate are the mosses. These are very easy to grow and only need something to attach themselves to. These could include driftwood, rocks or decorations in your tank. The most commonly used mosses are Java Moss and Christmas Moss. They are slow growing but easy to maintain and often spread easily.