Yellow Scroll Coral

Turbinaria reniformis is a stony coral that grows in thin, broad plates. The plates are mostly horizontal and form layers on top of each other over time. The surface is yellow-green, and the growing edges are usually a pale cream color. The polyps are small and sparsely distributed; when they open their short tentacles during the day, the surface looks slightly velvety.

With its hardiness, peaceful nature and tolerance of nutrients, it is a reliable species in mixed reef aquariums. Its trade is subject to CITES Appendix II; a large share of the Turbinaria sold are aquacultured frags, so choose those. T. mesenterina of the same genus forms more convoluted plates; the large-polyped "Turbinaria peltata" is now a separate species under the name Duncanopsammia peltata.

In the Indo-Pacific it forms large stands, especially on fringing reefs with turbid water. Living in turbid water explains why it tolerates somewhat elevated nitrate and phosphate in the aquarium and can also feed on particles in the water.

• Light: Moderate, about 100–300 PAR. It also survives in lower light, but the yellow color becomes pronounced under strong light.
• Flow: Moderate and variable. Detritus should not collect on top of the plates; if flow is insufficient, the tissue on the upper surface dies.
• Placement: The middle zone of the rockwork. Because the plates grow horizontally, they can shade the corals below and beside them; plan its placement according to its growth.
• Water parameters: Salinity 1.024–1.026, KH 7–10 dKH, calcium 400–450 mg/L, magnesium 1250–1350 mg/L. It is tolerant; it does well with nitrate at 2–15 mg/L and phosphate at 0.03–0.1 mg/L.

It is photosynthetic and gets most of its nutrition from light. Like its relatives in turbid waters, it also catches fine organic particles from the water; leftover fish food and regular water changes are usually enough. Target feeding is not needed.

It is a peaceful coral; it has no long stinging tentacles and rarely attacks its neighbors. The real problem is shading: the growing plates cut off the light of the corals beneath them. Since it is itself easily harmed by aggressive LPS, leave at least 15 cm of space between it and Euphyllia, Galaxea and the elegance coral.

Dwarf angelfish rarely pick at the plates. It lives without problems alongside most reef fish and invertebrates.

It is easy to propagate. A piece is cut or snapped off the edge of a plate with coral cutters and glued to a frag plug. The cut edge is soon covered with tissue. On the mother colony, cutting can also be used to control the direction of growth.

• Tissue loss on the upper surface: Usually caused by detritus collecting on the plate; increase the flow or clean the detritus away with a pipette.
• Algae under the plates: The shaded underside can grow algae; this is normal, but if it turns into tissue loss, review the flow.
• Fading color: Seen after a sudden change in lighting; change the light gradually.