How to Fix Slow-Growing Anubias: Light, Flow and Nutrient Tips

Anubias is famously marketed as a bulletproof aquarium plant, yet many hobbyists find their specimens barely producing a new leaf each month, with existing leaves covered in algae. If you want to fix slow growing anubias in your aquarium, the solution usually involves adjusting light, improving water circulation and addressing nutrient gaps. This guide from Gensou Aquascaping at 5 Everton Park, Singapore covers proven techniques for getting healthier, faster growth from this popular epiphyte.

Setting Realistic Expectations

Before troubleshooting, understand that anubias is genuinely a slow-growing plant. Even under optimal conditions, most anubias species produce one new leaf every 10-14 days. Anubias barteri var. nana is slightly faster, while large species like Anubias barteri var. barteri may take three weeks per leaf. If your anubias is growing at this rate with clean, dark green leaves, nothing is wrong. The concern arises when growth stalls entirely, leaves yellow or algae colonises the plant faster than it can produce new foliage.

Light: Less Is Often More

Anubias thrives in low to moderate light, around 20-40 PAR at the leaf surface. Ironically, excessive lighting is a more common problem than insufficient lighting. High light above 60 PAR accelerates algae growth on the broad, slow-growing leaves faster than the plant can outcompete it. Green spot algae, black beard algae and diatoms all flourish on anubias under strong light. Position anubias in shaded areas of the tank, under overhanging driftwood, beneath taller stem plants or in corners where light is naturally diffused.

Water Flow Around the Plant

Stagnant water around anubias promotes algae attachment and limits nutrient uptake. Position the plant where gentle filter outflow passes across the leaves, clearing debris and refreshing the boundary layer of water around each leaf. You do not need strong current; a soft, consistent flow is sufficient. Adjusting your filter outlet direction or adding a small circulation pump aimed at the anubias area can make a noticeable difference within weeks. In Singapore’s warm tanks, improved flow also helps with oxygenation around the plant.

Nutrient Requirements

Anubias draws nutrients entirely through its leaves and rhizome, not through roots in substrate. A comprehensive liquid fertiliser dosed weekly provides the potassium, iron and trace elements anubias needs. Deficiency shows as yellow patches on older leaves (potassium), pale new growth (iron) or pinholes developing across the leaf surface. Even low-tech tanks benefit from half-dose fertilisation. Products like Tropica Specialised Nutrition or 2Hr Aquarist APT Complete, both available in Singapore for $20-35, work well for anubias-focused setups.

Do Not Bury the Rhizome

This point cannot be overstated. Planting anubias with the rhizome buried in substrate causes rot, which manifests as mushy brown tissue, leaf die-off and stalled growth. The thick horizontal rhizome must sit exposed above the substrate or be attached to hardscape using superglue gel or fishing line. Roots can grow into substrate or crevices, but the rhizome itself needs water flowing around it. If your anubias has been buried, unearth it immediately and reattach it to a piece of driftwood or stone.

CO2 Injection: Helpful but Not Essential

Anubias grows without CO2 injection, which is part of its appeal for low-tech setups. However, supplementing with even a modest amount of CO2 at 10-15 mg/l noticeably accelerates leaf production and improves leaf size and colour. If a full pressurised CO2 system feels excessive for an anubias-centric tank, liquid carbon products like Seachem Excel provide a mild boost. Dose liquid carbon in the morning before lights come on for maximum benefit. CO2 also helps anubias outpace algae growth, which is arguably the bigger benefit.

Dealing With Algae on Anubias Leaves

Algae on anubias leaves is the most frustrating symptom of slow growth, as it creates a vicious cycle: algae blocks light, slowing growth further, which allows more algae to establish. For existing algae, introduce clean-up crew members like Amano shrimp (Caridina multidentata), nerite snails or otocinclus catfish. Three Amano shrimp per 20 litres provide meaningful grazing pressure. For stubborn black beard algae, spot-treat with a 3% hydrogen peroxide solution applied directly to affected leaves during a water change using a syringe.

Patience and Long-Term Results

Improvements in anubias growth take weeks to months to become visible, given the plant’s inherently slow pace. After making adjustments to light, flow and nutrients, allow at least six to eight weeks before evaluating results. New leaves produced under improved conditions will be noticeably larger, darker green and algae-free compared to older growth. Over time, a well-maintained anubias develops into a dense, compact clump that requires minimal intervention, rewarding your patience with one of the most attractive and enduring plants available to aquascapers in Singapore.

Related Reading

• How to Fix Algae on Slow-Growing Plants Like Anubias and Buce
• How to Fix Black Spots on Anubias Leaves in Aquariums
• Anubias Barteri Round Leaf Care Guide: Broad Circular Foliage
• Anubias Barteri var. Glabra Care Guide: Narrow Lance-Shaped Leaves
• How to Propagate Anubias Nana Petite: Rhizome Division Guide