Can Blackline Rasbora and Gold Nugget Pleco (L018) Live Together?

Blackline Rasbora is a peaceful species (1/10), while Gold Nugget Pleco (L018) is moderately assertive (6/10). This notable difference means Gold Nugget Pleco (L018) may occasionally assert dominance over Blackline Rasbora.

In terms of spatial distribution, Blackline Rasbora prefers the Middle (Open Water) and Top (Surface) zones, whereas Gold Nugget Pleco (L018) occupies the Bottom (Substrate) zone. Because they use different levels of the water column, territorial disputes are less likely and the tank will appear more balanced.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion. Aggressive eaters may outcompete shy fish for food, leading to malnutrition.

Worth noting: Blackline Rasbora is a known jumper, so a tight-fitting lid is essential.

There is no temperature overlap between Blackline Rasbora (22–26°C) and Gold Nugget Pleco (L018) (27–32°C). This fundamental mismatch makes long-term cohabitation impractical.

Both fish can tolerate a pH between 6 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 2–12 dGH. Regular testing will ensure conditions stay within this range.

To house Blackline Rasbora and Gold Nugget Pleco (L018) together, plan for an aquarium of at least 250 litres with a minimum length of 120 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.

Specific environmental needs for this combination include: Plants - Densely covered, Driftwood (Digestion/Hiding), Leaf Litter/Blackwater, Smooth Gravel (Sensitive Barbels), Established Algae (Otocinclus). Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.

Blackline Rasbora and Gold Nugget Pleco (L018) are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.

Feeding time deserves special attention with this pairing. Blackline Rasbora is an aggressive eater that may prevent Gold Nugget Pleco (L018) from getting enough food.

Because Blackline Rasbora is a fast, competitive feeder, consider using sinking pellets or feeding at opposite ends of the setup to ensure Gold Nugget Pleco (L018) receives an adequate share.