Pajama Cardinal

About this fish

The “Pajama Cardinal” is a marine cardinalfish sold under the scientific name Sphaeramia nematoptera. In a home aquarium, it’s appreciated for its calm, schooling-friendly demeanor and its habit of spending time in the water column—often using rockwork and cover to feel secure—while feeding on small, meaty foods. This listing focuses on group-level care guidance for cardinalfish in general and practical setup tips for keeping Sphaeramia nematoptera healthy.

Features:

• Peaceful temperament: typically compatible with other non-aggressive community tankmates
• Behavior: often prefers subdued lighting and cover, and may be most active around feeding
• Feeding approach: does best with small, protein-rich foods sized for a cardinalfish mouth
• Habitat use: favors aquascape with hiding spots and some open swimming space
• Water stability matters: thrives when temperature, salinity, and pH are kept steady
• Best results: introduce to an established system with good water quality and regular feeding

Specifications:

• Scientific name (as listed): Sphaeramia nematoptera
• Care level (general guidance): Moderate (needs stable marine water and properly sized foods)
• Temperament: Peaceful/community
• Light: Tends to prefer subdued lighting
• Water flow: Moderate
• Placement: Middle to lower areas near rockwork and cover
• Adult size: Up to ~10 cm (about 4 in)
• Diet: Small meaty foods (zooplankton-style foods; frozen/thawed options sized appropriately)
• Temperature: About 24–27°C (75–81°F)
• pH: About 8.1–8.4
• Salinity: About 1.020–1.025 specific gravity
• Water quality: Good filtration and steady parameters recommended