Mekongga Stream Goby (Lentipes Mekonggaensis)

A tiny rock-clinger built for torrents, gripping Mekongga’s streams against the current.

Meet the Mekongga Stream Goby (Lentipes mekonggaensis), a peaceful, algae-grazing goby for cool, fast-flow, mature stream biotopes and rocky aquascapes.

• Species overview and ideal aquarium setup: The Mekongga Stream Goby is a compact sicydiine goby built for life in rushing forest streams. It is not a fish for a brand-new aquarium: the best results come from a mature, biologically stable system with heavy biofilm growth on smooth cobbles and rounded stones. Set up a river-style tank with a sand or fine-gravel base, rounded rocks, cobbles, and driftwood; avoid sharp edges that can damage the goby’s skin as it grazes. Provide high water movement from a canister outlet, powerhead, or stream pump, but include calmer eddies and crevices where the fish can rest. A secure, tight-fitting lid is essential because stream gobies can climb and jump. Lighting should be moderate enough to encourage algae and biofilm without overheating the water. A tank of at least 60 cm/24 inches is a sensible minimum for a small group, with more length and flow preferred. This species is amphidromous in the wild, so captive breeding is not expected; aquarium care should focus on long-term health and natural grazing behaviour.
• Water conditions: Aim for cool, clean, highly oxygenated water: temperature around 20–24°C (68–75°F), pH 6.5–7.8, general hardness around 4–12 dGH, and carbonate hardness around 2–8 dKH. Ammonia and nitrite must remain at zero, and nitrate should be kept low, ideally below 20 ppm, through regular partial water changes and careful stocking. These gobies are sensitive to low oxygen and stagnant water, so surface agitation and flow are not optional. Use a reliable heater only as a safety net; avoid warm-water conditions and sudden temperature swings. Keep parameters stable rather than chasing exact numbers, and test regularly during the first few months. A mature filter, porous biological media, and good circulation will help maintain the pristine water this species demands. If you use medications, use them cautiously and only when necessary, as stream gobies can be sensitive to harsh treatments.
• Suitable tank mates: Choose peaceful, cool-water, rheophilic companions that will not outcompete the goby for biofilm or harass it. Other small stream gobies, such as appropriately housed Stiphodon or Rhinogobius species, can work in a spacious, well-structured river setup, as can small temperate minnows like white cloud mountain minnows. Avoid large, boisterous, or predatory fish, warm-water community species, cichlids, and bottom-dwellers that disturb the substrate or monopolise food. Crayfish and aggressive crabs are unsuitable. Shrimp may be safe in a mature tank, but very small shrimp fry could be picked off. If keeping multiple gobies, provide plenty of visual barriers and grazing surfaces; males may spar over territory, especially in smaller tanks. Do not mix too many algae-grazing species in a limited space, because competition for aufwuchs can lead to malnutrition.
• Feeding habits: In the wild, the Mekongga Stream Goby grazes on biofilm, algae, and the tiny organisms living on rocks. In the aquarium, a mature tank with visible biofilm is the foundation of its diet, but do not rely on algae alone. Offer small amounts of spirulina-based wafers, algae pellets, Repashy Soilent Green or similar gel foods, and blanched zucchini, spinach, or cucumber. Powdered algae and finely crushed algae wafers can help supplement grazing surfaces. Some specimens accept small meaty foods such as baby brine shrimp or microfauna, but keep these occasional; the diet should remain predominantly plant- and algae-based. Feed two or three small portions daily, removing uneaten food to protect water quality. Observe the fish’s belly and grazing activity: a sunken belly or constant glass-surfing can indicate insufficient biofilm or competition. Rotating foods and target-feeding near grazing rocks will help ensure every goby gets enough.
• Care, acclimation, and long-term health: Acclimatise new arrivals slowly with a drip method, matching temperature and water chemistry before release. Quarantine where possible and avoid adding them to an immature tank. Once settled, maintain a consistent routine: weekly water changes of around 25–30%, gentle substrate cleaning, filter maintenance, and regular checks of flow and oxygen. Keep the lid secure, as these gobies can climb. Provide smooth, algae-covered rocks and caves; sharp décor can cause abrasions. Watch for signs of stress such as clamped fins, rapid breathing, hiding, or weight loss. Because many stream gobies are wild-caught, choose healthy, active specimens and give them a calm, well-oxygenated tank. Long-term success depends on stable cool water, strong current, abundant biofilm, and low competition. With the right river-style setup, the Mekongga Stream Goby is a fascinating, peaceful grazer that adds natural behaviour and subtle colour to a specialist aquascape.