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Shop Crushed Lava Rock Gravel Substrate - Glass Aqua

Crushed Lava Rock Gravel

$34.99 USD
Usually ships in 1-2 business days from our fulfillment center

Lava Rock Gravel may be used for a wide variety of purposes. We recommend using it as an accent to a Black Lava Rock aquarium hardscape layout, filtration media, or as a tank substrate! The possibilities are endless! This lava rock gravel is inert and will not change water parameters.

Black Lava Rock is a classic aquascaping stone that's often used in all types of aquarium setups such as planted tanks, freshwater, and brackish. Because of its highly porous nature, easy aquatic plants like moss, Anubias, Ferns, and Bucephalandra will readily attach themselves to these rocks. In addition, it's also great for the colonization of beneficial bacteria resulting in a healthier aquarium environment. 

Ultum Nature Systems 45S Shallow Rimless Planted Aquarium Tank

TIP: Rinse before use. 

Aquarium Substrate Comparison Guide

Sand, gravel, and aquarium plant soil can all be used to grow aquatic plants. But are they the same? The short answer is no. Here’s our take on each substrate type.

Ultum Nature Systems 45U Standard Rimless Glass Aquarium Tank Ultum Nature Systems Standard Rimless Glass Aquarium Tank
Before
After

3 different freshwater aquarium substrates used in a 9 gallon nature-style aquascape

Natural Cosmetic Sand

Aquarium sands are suggested for cosmetic purposes only and are usually paired with aqua soil when creating a nature-style aquarium. In some cases, hobbyists might choose natural sand as a main substrate and add nutrients back in via aquatic plant root tabs. This is enough to feed some low-tech aquarium plants. However, it isn’t sustainable long term since they dissolve and deplete quicker than plant soil. If you want a full sand look, try adding a base layer of soil first then topping it with your preferred sand. This way, you don’t miss out on the added benefits of aquarium soil and your aquatic plants get the nutrients they need. Overall, natural sand is an aquascaping staple. It’s available in many colors and also provides enrichment for bottom-dwellers who enjoy sifting through!

Optional hot tip: Use a sand flattener or brush to create a 0.5-1” gap between your soil layer and the tank panels. Then, pour your sand on top for extra clean edges. No soil peeking through here!

Ultum nature systems UNS Controsand Bora aquarium sand

Ultum Nature Systems Controsand Bora is a bright natural fine sand that works well with all freshwater aquariums

Ultum nature systems UNS 5N Nano Rimless Glass Aquarium Tank Betta Fish Aquascape
Sand is great for minimalistic aquascapes that do not require plants to be rooted into soil
Ultum nature systems UNS 20C Cube Rimless Glass Aquarium Tank Iwagumi Betta Fish Aquascape
It can also provide great contrast to bolder aquarium hardscape layouts
Ultum nature systems UNS 20C Cube Rimless Glass Aquarium Tank Iwagumi Betta Fish Aquascape
Lighter sands add brightness to aquariums
Ultum nature systems UNS 20C Cube Rimless Glass Aquarium Tank Shimp Iwagumi Aquascape
It is also great for sand sifting aquarium livestock such as Neocaridina Shrimp
Corydoras fish sifting through planted aquarium sand
Aquarium fish like Corydoras naturally love sifting sand
Aquarium Gravel

Like sand, gravel is another aquascaper’s choice. We’ve heard them used interchangeably, but they’re not the same! Gravel is a chunkier medium and can be used independently or as detail accents on top of a fine-grain sand base. Depending on your tank size, gravel may be a better option as it covers more surface area as well. Personally, we really enjoy using gravel as an accent in our aquascapes as sometimes sand alone can look too plain. A sprinkle of gravel here and there really adds that extra bit of fine detail that can elevate the entire look of a nature-inspired aquascape. Here are some of our previous tanks with gravel being used as an accent vs. a gravel-only planted tank.

Ultum nature systems UNS Controsand Santa Fe natural gravel

Ultum Nature Systems Controsand Santa Fe features a mix of dark and light natural hues that are perfect for river-type aquascapes

Ultum nature systems UNS 25C Cube Rimless Glass Aquarium Tank Dutch Wabi Kusa Aquascape
Gravel used purely for cosmetic purposes in a cube aquarium
Ultum nature systems UNS 45E Rimless Glass Paludarium Tank
It can also be used in paludarium aquascapes as well
Gravel like sand, can come in various earthy hues
Ultum nature systems UNS 75S Shallow Rimless Glass Aquarium Tank Paludarium Aquascape
It can also be used in much large aquariums where sand would not make the same visual impact
Ultum nature systems UNS 16C Cube Rimless Glass Aquarium Tank
Gravel is widely used as a decorative substrate in wabi kusa style aquariums
Ultum nature systems UNS Controsand Bora and Monterey aquarium sand and gravel

A mix and match of Ultum Nature Systems Controsand Bora (sand) and Monterey (gravel)

Hakkai Stone Planted Aquarium Tank Aquascape
A combination of sand and gravel accents in a planted aquarium
Ultum nature systems UNS 5N Nano  Rimless Glass Aquarium Tank
Mix and match sand and gravel accents for a unique look
Ultum nature systems UNS 45U Standard Rimless Glass Aquarium Tank
Matching Controsand Vesuvius crushed lava rock with lava rock hardscape
Ultum nature systems UNS 60S Shallow Rimless Glass Aquarium Tank
We match the accent gravel with hardscape often to create a uniform look
Aquatic Plant Soil

The term aqua soil generally encompasses any substrate that contains nutrients and is designed specifically for tropical freshwater aquarium use. These aquarium plant soils usually contain micro and macronutrients or may offer features like dormant beneficial bacteria and water buffering capabilities. This is why rinsing prior to use isn’t recommended! Doing this washes away some of the good stuff that plants love. Popular aquarium plant types like Echinodorus, Cryptocoryne, various stem plants and Vallisneria species reap the best benefits from aquatic plant soil. Using them also supports the proper cycling of a new tank. 

Ultum nature systems UNS Controsoil Extra Fine Black aquarium plant soil Ultum nature systems UNS Controsoil Fine Black aquarium plant soil Ultum nature systems UNS Controsoil Normal Black aquarium plant soil
EXTRA FINE
FINE
NORMAL

You’ll notice higher quality soils usually contain natural ingredients like volcanic ash and clay, which are then high pressure baked into granules. The spherical shape prevents your soil from turning into mud over time and can be useful when creating slope hills in your aquascape. Some aquarium substrates like Ultum Nature Systems Controsoil, come in two different colors and three granule sizes. The soil’s ingredients are the same, but choosing the correct granule size is important and can be game changing. Carpeting aquarium plants like Glossostigma elatinoides, Hemianthus callitrichoides ‘Cuba’, Micranthemum ‘Monte Carlo’, and Eleocharis (dwarf hairgrass) varieties are much easier to plant in extra-fine substrate types. The smaller granule also makes it easier for the plant’s roots to take hold and become established. On the flip side, large root aquarium plants like amazon swords (Echinodorus sp.) and jungle vals (Vallisneria sp.) will be easier to plant and root in larger soil granules.

Using aquarium soil, sand, and gravel while sloping it towards the back of the aquarium without mixing

There you have it! One important thing to note is that aquarium soils don’t last forever. In general planted tank conditions, most quality soils will last between 8-12 months before depletion. When you reach this point, here are some of the common options:

  1. Revitalize the soil with aquarium plant root tabs!
  2. Keep the same scape, remove some plants, top off with a fresh soil layer and replant.
  3. Use this as an opportunity to do a full rescape.
Choose your Aquarium Substrate
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