JBL Sansibar Dark Aquarium Sand - 5 kg

JBL Sansibar Dark Aquarium Sand - 5 kg is a fine dark granite sand for freshwater and marine aquariums.

Key Features

• A dark bed makes fish look like themselves: This is the biggest single visual change you can make to a tank, and it costs nothing extra. Over pale sand most fish go pale and stay jumpy. Over a dark floor they colour up and settle, because in the wild a bright bottom means being exposed.
• 0.2 to 0.6 mm fine granite sand: Fine enough for corydoras and loaches to sift through properly, and dense enough to hold plant roots without setting into a solid block.
• No light bouncing back up: JBL make the point themselves: a dark substrate kills the upward reflection that unsettles nervous fish, so they show their natural colouring instead of blanching.
• Inert, so it changes nothing: A natural granite and quartz sand does not move pH or hardness. Whatever water your fish need, the bed will leave it alone, which is the whole difference between a sand like this and an active plant soil.
• Gentle on barbels and bellies: Round grains rather than crushed chips. Corydoras, loaches and the other fish that sift the bottom wear their barbels away on sharp gravel and then pick up infections in the damage, which is the usual reason a catfish ends up with stumps instead of whiskers.
• Keeps waste on the surface: A dense, fine bed stops mulm and uneaten food working down out of reach, so it lifts out with a siphon instead of rotting somewhere you cannot get at it.

Choosing Between The Sansibar Sands

• Grain size decides who can live on it. The fine grades at around 0.2 to 0.6 mm are what sand sifting fish such as corydoras and loaches need. River, at 0.8 mm, is the coarsest and suits larger diggers. Snow is the finest in the range.
• Colour decides how your fish look. Over a dark bed most fish show their full colour and behave calmly. Over white or pale sand, light bounces up off the floor and the same fish often look washed out and stay nervous, which matters most with shy and wild caught species.
• They are all inert, so none of them shifts pH or hardness and all of them are safe with any stock. That is quite different from an active plant or shrimp soil, which changes the water on purpose.
• In a planted tank the sand is the top layer only. A nutrient substrate such as AquaBasis Plus or FloraPol goes underneath it.

How Much You Will Need

• Work out the volume first. Length times width times the depth you want, all in centimetres, divided by one thousand, gives litres of substrate.
• Sand weighs roughly one and a half kilos a litre, so multiply the litres by 1.5 to get kilos.
• A 60 by 30 cm tank at 5 cm deep comes out at about nine litres, which is around thirteen kilos, so nearly three 5 kg bags. A 100 by 40 cm tank at 6 cm needs about twenty four litres, or roughly thirty six kilos.
• Order slightly over rather than under. Blending a different batch into an established bed later never quite matches, and you will want spare when you rescape.

Depth, And Why It Matters

• Three to five centimetres is plenty for a sand only tank. Six to eight centimetres over a nutrient layer is what strong rooted plant growth needs.
• Fine sand much deeper than about five centimetres, left completely undisturbed, will go anaerobic in patches. You see it as black or grey areas against the glass, and it smells of rotten eggs when disturbed, because it is producing hydrogen sulphide. Releasing a large pocket in one go can kill fish.
• Avoiding that is simple. Keep the bed shallow, or run your fingers through the top couple of centimetres at water change time, or keep Malaysian trumpet snails, which turn the sand over for you continuously.
• Rinse the sand in a bucket until the water runs clear before it goes anywhere near the tank, or you will be looking at milky water for days.
• Keep filter intakes well clear of the bed. Sand drawn into an impeller will ruin it, and a scored impeller is the one fault a canister filter does not shrug off.

Good To Know

• If you keep anything shy, wild caught or strongly coloured, this is the sand to buy before any of the pale ones.
• JBL list the range for marine tanks as well as fresh water, and it is inert and safe there. Be aware that a granite or quartz sand does no buffering at all, so if you want the bed itself to help hold reef alkalinity up, you need an aragonite sand instead and this is not one.
• Adding sand to a tank that is already running: lower it to the bottom in a jug or a bag and tip it out down there, rather than pouring it through the water and clouding the whole tank.
• Also used in aqua-terrariums and paludariums, where the same round grains suit shoreline and burrowing species.