JBL ProScape Volcano Mineral Base Substrate - 3L

JBL ProScape Volcano Mineral Base Substrate is a porous volcanic rock base layer for aquascaping, laid under the soil to anchor hardscape and keep water moving through the bed.

Key Features

• A base layer, not something you plant into: Volcano goes at the very bottom. It is there to build the height and the structure of a layout, with soil or sand over the top, and it means you are not filling a tall slope with expensive soil.
• Rock and wood stop sliding: The angular porous pieces interlock, so a stone or a piece of wood bedded into them stays where you put it. Set a steep hardscape on loose sand and it slumps within weeks.
• Keeps the deep bed alive: Open pored rock at the bottom lets water and oxygen move through the lowest layer, which is exactly where a deep substrate otherwise goes anaerobic and starts producing hydrogen sulphide.
• Holds minerals in the root zone: The pore structure stores minerals and nutrients down where deep roots reach, and gives bacteria a large surface to colonise.

Building A Layout On It

• Volcano at the bottom, shaped into the slopes and terraces you want. This is where the height of a scape comes from.
• Soil or nutrient substrate next, then a sand or gravel cap on top if you want one.
• Bed your main rocks and wood down into the volcanic layer rather than standing them on the soil, so they are sitting on something that will not settle under them.
• Use it to fill the volume behind a terrace or under a hill. Filling that space with soil is expensive and gives you a very deep organic bed that will go sour.
• Keep the total bed to around eight centimetres where it is visible at the front, and put the depth at the back where a tall scape needs it.

How Much You Will Need

• Length times width times the depth you want, all in centimetres, divided by one thousand, gives the litres you need.
• A 60 by 30 cm tank at 5 cm deep works out at about nine litres, so one 9 litre bag or three of the 3 litre ones.
• As a base layer this is usually two to four centimetres across the flat areas and a great deal deeper behind a terrace, so measure the shape you are actually building rather than the tank footprint.
• Buy the whole amount at the start. Adding base material later means lifting the soil and the planting off it first.

Good To Know

• Rinse it before use. Volcanic rock carries a lot of fine dust and will cloud a tank for days otherwise.
• It is sharp and angular, so it is a base layer rather than a surface for corydoras or loaches to work over. Cap it with sand if you keep bottom dwellers.
• Do not count it as plant nutrition on its own. Pair it with a nutrient layer underneath or with liquid dosing.
• Sold in 3 litre and 9 litre bags. A terraced scape eats base material faster than you expect, so measure the volume you are filling before you order.