• The densest Eco-Complete Cichlid grade - at 72 lb per cubic foot each grain is substantially heavier than the black grade at the same 4.0 to 10.0 mm size, so a digging fish rearranges less of it.
• Aragonite based - it adds calcium, magnesium and carbonate, and CaribSea states it buffers automatically for the life of the aquarium.
• Live bacteria in the bag - supplied damp and biologically active, so a new bed begins processing ammonia sooner than dry gravel would.
• No rinsing - it is packed in a water conditioning solution that removes chlorine and chloramine. Rinsing discards both that and the bacteria.
• Natural mixed tone - a neutral bed that does not show pale detritus the way a black substrate does, and does not bounce light the way a white one does.
• Large open pore spaces - water moves through a coarse bed rather than sitting in it, so the lower layer does not go stagnant at sensible depths.

Cichlid Gravel is the heaviest of the three grades per litre of bed, so the same tank takes more kilograms than it would in the black grade. The table gives the weight and the number of 9.072 kg bags for common Australian tank footprints, worked from CaribSea's published bulk density of 72 lb per cubic foot (1.15 kg per litre of bed).

How these figures are worked out

CaribSea publishes a bulk density for every substrate. Bed volume is the tank footprint multiplied by the depth you want, and the weight is that volume multiplied by the density. Bag counts are rounded up to the next whole bag.

Two practical adjustments. Rockwork and caves sitting on the glass displace substrate, so a heavily scaped tank needs a little less than the table says. A bed that slopes from front to back needs the average depth, not the deepest point.

We also stock CaribSea Eco-Complete White Cichlid if you want a bright bed rather than a natural or dark one.

The honest answer is that it depends on the fish, not on looks. Most Malawi haps and mbuna move substrate around as a matter of routine, and a 0.5 to 1.5 mm sand ends up in drifts against the glass within weeks. A 4.0 to 10.0 mm grain at 72 lb per cubic foot resists that.

The cost of choosing gravel is cleaning. Pellets and detritus drop into the gaps between grains instead of sitting on the surface where a siphon can lift them off, so this grade needs the vacuum pushed into the bed rather than skimmed over it.

Shell-dwelling Tanganyikans are the clear exception. They need a fine sand they can actually excavate and pile, and gravel this size makes their natural behaviour impossible.

Suitable for: Lake Malawi mbuna and hap aquariums; larger Tanganyikan community tanks; Central American cichlids that want hard alkaline water; any hard-water freshwater tank where pH drifts down between water changes.

Not suitable for: planted aquariums, soft-water community tanks, blackwater and Amazonian setups, shrimp tanks, and discus or apistogramma systems - aragonite raises pH and carbonate hardness and that cannot be switched off. It is also unsuitable for shell dwellers and any sand-sifting species, and a poor choice as a deep bed, where the gaps collect detritus a siphon cannot reach.

1. Put the gravel into an empty tank first, and pour in the liquid from the bag with it - that liquid is the water conditioner and the bacterial culture.
2. Level it, then bed rockwork and caves directly on the glass wherever possible so nothing topples when a fish digs beneath it.
3. Add water slowly onto a plate or a bag laid on the gravel rather than straight onto the bed.
4. Run filtration. Some cloudiness is normal and clears as the filter catches the fines.

Work the gravel vacuum down into the bed at each water change rather than passing it over the surface. Coarse substrate hides waste rather than displaying it, so a bed that looks clean often is not.

Keeping the depth to 2.5 to 5 cm is what makes that practical. At 7.5 cm and beyond you cannot get a siphon to the glass, and the lower layer becomes a store of detritus with no way to service it.

Buffering capacity is consumed very slowly as aragonite dissolves, so there is no replacement interval. Top up if the bed drops noticeably over several years.

• CaribSea Eco-Complete Cichlid Sand - the fine grade, useful as an open sand patch in front of a rock wall.
• Dragon Stone Freshwater Rock - pitted rock for the caves and territory breaks that mbuna tanks are built around.
• API Cichlid Pellets Medium 120g - a staple pellet for the mixed Rift Lake communities usually kept over this bed.

CaribSea does not publish a warranty term for its substrates. Your rights under the Australian Consumer Law apply regardless, and are not limited by anything the manufacturer does or does not offer.

Each bag weighs 9.072 kg, and this is the heaviest grade per litre of bed. A 180 x 60 cm tank at 5 cm depth is seven bags, a little over 63 kg, so check the freight total before ordering a full bed.

Do I need to rinse CaribSea Eco-Complete Cichlid Gravel?

No. It is supplied damp in a water conditioning solution with live bacteria, and CaribSea's instruction is to place the contents straight into the aquarium. Rinsing removes the conditioner and the bacterial culture.

Will my cichlids still dig it up?

They will move it, but far less than a sand. At 4.0 to 10.0 mm and 72 lb per cubic foot this is the heaviest grade in the range, and it is the best of the three at holding a slope or a contoured bed against routine digging.

Does it need a gravel vacuum or is surface siphoning enough?

It needs a vacuum worked into the bed. Waste falls into the gaps between 4 to 10 mm grains rather than resting on top, so surface siphoning removes very little of what is actually there.

How does it compare with Black Cichlid?

Same 4.0 to 10.0 mm grain, different colour and density. Cichlid Gravel is natural toned at 72 lb per cubic foot; Black Cichlid is black at 54. The gravel resists digging better; the black grade needs fewer kilograms for the same bed depth.

Can I keep shell-dwelling cichlids over it?

No. Shell dwellers such as Neolamprologus multifasciatus excavate and bank substrate around their shells, and a 4 to 10 mm grain is far too large for them to shift. Use Eco-Complete Cichlid Sand for those tanks.

Will it work in a planted tank?

No. It raises pH and carbonate hardness, which is the opposite of what most aquarium plants want. Eco-Complete Planted Red is the equivalent coarse grade for a planted tank and is carbonate free.