Malboro lobster 5 - (Cherax quadricarinatus) — 5-6cm

Overview

Cherax quadricarinatus, commonly known as the Redclaw Crayfish or Marlboro Lobster, is a striking semi-aggressive Australian crayfish that brings bold red coloration and impressive personality to secure species-focused aquariums. Available for sale UK through Tropical Fish Co, this species reaches 5cm in the juvenile size offered though grows substantially larger at maturity. The moderate care level and semi-aggressive temperament make it suitable for experienced aquarists prepared to provide appropriate accommodation with robust tankmates or species-only setup. The species' vibrant red coloration and fascinating behaviour create captivating display when properly housed.

Appearance and Red Coloration

The Redclaw Crayfish displays impressive crayfish morphology with robust carapace, segmented abdomen, and characteristic two substantial chelipeds (claws). The species' most distinctive feature is vibrant red coloration on claw joints giving rise to the "redclaw" common name—this marking becomes particularly pronounced in mature males. Overall body coloration ranges from olive-brown to blue-grey with variable patterns. The claws are well-developed and powerful, used for defense, food manipulation, and territorial disputes. Four pairs of walking legs provide locomotion, whilst long antennae and shorter antennules provide sensory information. The exoskeleton must be periodically moulted for growth. Males develop distinctive red patches on outer margins of claws and broader larger claws overall compared to females.

Natural Habitat

Cherax quadricarinatus inhabits freshwater rivers, streams, billabongs, and wetlands throughout northern Australia and southern New Guinea. These tropical environments feature warm stable temperatures, varied substrates from mud to rocks, and abundant aquatic vegetation providing cover and food sources. Natural habitats typically have neutral to slightly alkaline water chemistry. The species occupies areas with hiding places under rocks, logs, and within vegetation, emerging to forage primarily during nocturnal periods. The omnivorous diet includes aquatic vegetation, detritus, aquatic invertebrates, small fish, and carrion. Seasonal variations bring changes in water levels though temperatures remain tropical year-round in native range.

Aquarium Setup

Provide minimum 60-litre aquarium for juvenile specimens, though substantially larger (100+ litres) required as they mature. Use sand or fine gravel substrate allowing some natural burrowing behaviour. Furnish extensively with caves, PVC pipes, rock arrangements with secure stable construction, and driftwood creating numerous hiding places—essential during moulting periods when crayfish are vulnerable. Avoid delicate live plants as these will be damaged through digging and consumption; hardy robust species like Anubias may survive, or use artificial plants. Powerful efficient filtration is essential given messy feeding habits and substantial waste production. Secure tight-fitting heavy lid is critical—Redclaw crayfish are excellent escape artists capable of climbing vertical surfaces and exploiting any gap. Ensure all equipment is secured as they may attempt to climb or dislodge filters and heaters.

Water Parameters and Quality

Maintain stable temperatures between 22-28°C reflecting tropical origins. Water should be neutral to slightly alkaline with pH 6.5-8.0 and moderate hardness (8-15 dGH) supporting exoskeleton calcification and moulting success. Ammonia and nitrite must remain at zero, with nitrates maintained below 30ppm through regular substantial weekly water changes of 30-40%. These reasonably hardy crayfish tolerate moderate parameter variations but consistency prevents stress particularly during moulting periods. Good oxygenation through surface agitation is important for metabolic health. Provide mineral supplementation through cuttlebone or specialized crayfish minerals—calcium and mineral availability directly impacts successful moulting and exoskeleton development. Deficiencies cause moulting difficulties potentially fatal.

Feeding and Omnivorous Diet

Cherax quadricarinatus is an opportunistic omnivorous scavenger requiring varied balanced diet. Provide quality sinking crustacean or omnivore pellets as daily staple, supplemented with blanched vegetables (courgette, spinach, peas), algae wafers, and occasional protein foods such as frozen bloodworms, chopped earthworms, small pieces of fish, or shrimp 3-4 times weekly. Feed in moderate portions—crayfish are messy feeders that scatter food whilst manipulating it. Remove uneaten food after 24 hours to prevent water quality degradation. Reduce feeding immediately before and during moulting periods when appetite naturally decreases. Calcium-rich supplementation through cuttlebone or mineral blocks supports exoskeleton health particularly during growth phases. Varied diet ensures nutritional completeness and supports vibrant coloration development.

Behaviour and Semi-Aggressive Nature

Redclaw Crayfish display semi-aggressive territorial behaviour more moderate than some crayfish species but still requiring careful management. They establish territories around preferred hiding places, defending against intruders through claw displays and physical confrontation if necessary. Primarily nocturnal, they emerge from hiding during evening hours to forage, though bolder individuals may appear during daytime feeding. Activity includes territory patrolling, foraging, substrate excavation, decoration rearrangement, and persistent attempts to escape—they continuously test aquarium perimeter. Toward tankmates, behaviour ranges from indifferent tolerance of large fast fish to opportunistic predation on smaller slower species. Moulting occurs periodically requiring secure hiding place for vulnerable period whilst new exoskeleton hardens. Inter-crayfish aggression can be significant particularly between males.

Compatible Tank Mates

Due to semi-aggressive nature and predatory tendencies, tankmate selection is challenging. Species-only setup or very carefully chosen robust tankmates in large well-structured aquariums only. If tankmates attempted, select only similarly sized robust species occupying different zones, extremely fast swimmers, and fish too large to be grabbed (minimum 8-10cm). Potential companions might include large robust barbs, substantial fast tetras, or peaceful surface-dwelling fish. Absolutely exclude small fish (eaten), shrimp (consumed immediately), snails (crushed), slow or long-finned fish, bottom-dwelling fish overlapping territory, and definitely other crayfish unless in extremely large systems with extensive separate territories (even then aggression likely). The destructive nature toward plants and opportunistic predation means realistic assessment favours species-only accommodation for best welfare and lowest tankmate risk.

Breeding

Cherax quadricarinatus breeds readily in captivity when kept in suitable conditions with appropriate hiding places. Sexual dimorphism in mature specimens: males develop distinctive red patches on claw margins, possess larger broader claws, and show narrower abdomen compared to females' broader abdomen for egg carrying. Breeding follows mating where male fertilizes female, who then carries developing eggs attached to swimmerets under abdomen. Egg carrying period lasts several weeks with female remaining relatively hidden during this vulnerable time. Juveniles hatch as miniature versions of adults, initially clinging to mother before becoming independent. Separate juveniles by size to prevent cannibalism—they grow at different rates and larger siblings may consume smaller ones. Juveniles require their own hiding places and grow rapidly with adequate food and calcium, moulting frequently during early life.

Why Buy from Tropical Fish Co

Tropical Fish Co supplies healthy, active Cherax quadricarinatus specimens that have been carefully maintained in appropriate conditions. Each Redclaw is hand-selected for good body condition, vibrant developing coloration, and intact appendages, ensuring you receive robust crayfish ready to thrive in properly designed aquariums. Our experienced staff understand the semi-aggressive nature and specific requirements of these crayfish and can provide realistic guidance on compatible tankmates (very limited options), appropriate tank sizing, and long-term care strategies. With specialist packaging ensuring safe transit and next-day UK delivery, your new crayfish arrives in excellent condition. We're committed to sustainable sourcing and work only with responsible suppliers prioritizing invertebrate welfare and providing captive-bred specimens.