Crushed Lava Rock
Also sold as lava gravel · lava rock · crushed lava · lava granules · Controsand Vesuvius (UNS lava-style gravel) · UNS Controsand Vesuvius · Controsand Vesuvius · Crushed lava rock gravel
Crushed Lava Rock from generic is a gravel with a 3–12 mm grain. It holds no nutrients of its own, which is what decides whether it suits your plants and your shrimp.
Calculate substrate quantity before buying materials.
At a glance
| Type | Gravel |
|---|---|
| Nutrients | None (inert) |
| Grain | 3–12 mm |
| Brand | generic (e.g. SubstrateSource, Glass Aqua) |
| Effect on pH | Neutral |
| Ammonia when new | None |
| Shrimp | Suits Neocaridina |
Shown at real grain size, about 16 cm across
Before it goes in
- Crushed Lava Rock is a gravel, 3–12 mm grain.
- It is inert: it holds no nutrients of its own. Root feeders such as Cryptocoryne wendtii and Dwarf Hairgrass Mini need root tabs under them.
- It is pH-neutral: whatever comes out of your tap is what the tank sits at.
- It releases no ammonia, so livestock can go in as soon as the tank is cycled.
- Carpeting plants struggle to root in it: the grain is too loose or too large to hold their runners.
- It is rough on fish that sift the substrate. Something finer suits German Blue Ram and Julii Cory better.
- It suits Neocaridina, which want harder water than Caridina do.
Crushed Lava Rock: care and setup
What kind of substrate is it?
Gravel with a 3–12 mm grain, holding no nutrients of its own.
Does it change pH?
No — it is inert and leaves your tap water where it is.
Does it leach ammonia?
No, so you are not waiting on it to stop before stocking.
Can I use it on its own?
Yes — Crushed Lava Rock is a complete substrate on its own.
Will carpeting plants root in it?
Not easily. Runners struggle to get a hold in it.
What it goes with
- Plants that do not care that it is inert, because they feed from the water: Hygrophila corymbosa 'Siamensis', Water Sprite, Anubias nana 'Petite' and Frogbit.
- Animals that are fine on it: Betta, Cherry Shrimp, Goldfish and Angelfish.
Often compared with
| Crushed Lava Rock | Colored Gravel | Dennerle Crystal Quartz Gravel | |
|---|---|---|---|
| Type | Gravel | Gravel | Gravel |
| Nutrients | None | None | None |
| pH | Neutral | Neutral | Neutral |
| Grain | 3–12 mm | 3–6 mm | 1–2 mm |
| Leaches ammonia | No | No | No |