Red Rili Shrimp Breeding Guide

Red Rili is a Neocaridina davidi color morph that breeds readily in freshwater; its red-and-clear pattern requires culling to stay sharp across generations.

Overview

Red Rili is a color morph of Neocaridina davidi, a freshwater dwarf shrimp of the family Atyidae native to China and Taiwan. The "rili" pattern shows colored head and tail sections separated by a translucent midsection. All Neocaridina varieties are the same species, so Red Rili breeds as easily as any other morph; adults reach roughly 3-4 cm and live about 1-2 years.

Telling Males from Females

Females grow larger (up to about 4 cm), are more strongly colored, and have wider tails; males stay smaller (about 2.5-3 cm) and more translucent. A mature female shows a yellowish saddle of developing eggs on her back. A group of at least ten shrimp reliably contains both sexes.

Breeding Conditions

A sexed group in a predator-free tank breeds readily. Reported limits are 16-28 C (60-82 F), most comfortable 22-24 C (72-76 F), pH 6.5-8.5, GH at least 6 dGH (110 ppm) and KH at least 2 dKH (40 ppm). Mineral-rich water is needed for successful molting; soft water can cause failed molts. Maturity is reached at about two months.

Eggs & Young

After molting and mating the berried female carries 20-30 eggs attached to her swimmerets, which darken over roughly 2-3 weeks before hatching. There is no larval stage; young hatch as tiny copies of the adults, around 1 mm long, and the adults do not eat their own young.

Maintaining the Pattern

The rili pattern is unstable and drifts without selection. Breeders cull individuals with poor patterning or weak red so that only the best-marked shrimp reproduce. Mixing different morphs tends to produce offspring that revert toward wild-type brown.