Can Masked Julie (Julidochromis) and Royal Pleco (L190) Live Together?

Masked Julie (Julidochromis) is a moderately assertive species (6/10), while Royal Pleco (L190) is moderately assertive (5/10). This modest difference means Masked Julie (Julidochromis) may occasionally assert dominance over Royal Pleco (L190).

Masked Julie (Julidochromis) and Royal Pleco (L190) both frequent the Bottom (Substrate) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Additional behavioural considerations to keep in mind: Two territorial species may clash over territory, especially in smaller tanks.

Worth noting: Royal Pleco (L190) is nocturnal and will be most active after lights-out, naturally reducing daytime encounters.

The safe temperature window for both species falls between 23°C and 27°C. Aim for the midpoint of this range (around 25.0°C) for optimal comfort.

The pH requirements of Masked Julie (Julidochromis) (8–9) and Royal Pleco (L190) (6.5–7.5) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 10–15 dGH. Regular testing will ensure conditions stay within this range. An aquarium test kit is recommended for monitoring.

To house Masked Julie (Julidochromis) and Royal Pleco (L190) together, plan for an aquarium of at least 540 litres with a minimum length of 150 cm. This accounts for the larger species' space requirements with an additional 20 % buffer to reduce territorial tension.

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: Sand (Sifters), Driftwood (Digestion/Hiding). 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.