Why are my Red Cherry Shrimp so pale?
Red cherry shrimp (Neocaridina heteropoda var. red) originate from Taiwan. They have been specifically bred to lack some pigment and so display a red color. This variety are often kept in aquariums. They are best kept at 60–85 °F and reach an adult size of about 15 inches long. They live for about two years under optimal conditions.
People are often disappointed at the color of their shrimp, in which case here are some things to consider.
Young shrimp
Cherry shrimp are usually quite pale as juveniles so if your shrimp are under half an inch in size, pale color is quite normal. Most people purchase juveniles as they adapt better to being shipped and relocated. So your new stock won't look like the illustrative photographs provided by the breeder or retailer until they have a chance to grow up.
Males
While some people manage to get good color in the male shrimp it is not uncommon for them to be only red in speckles or bands. Males are generally smaller and have a more tapered body shape. Females can be spotted as they grow by a yellow mass in the thorax.
Stock
It is a good idea to see the stock you are buying from, and not just the best specimens. Genetics has some influence on coloration.
Settling Time
General stress can cause shrimp to became pale, but they will color up when they relax.
Realistic Expectations
Keep in mind that only prime adult females tend to appear in promotional material. Even the best population of shrimp will not be made up entirely of fully red specimens.
So can I make the more red?
Yes! Please read on.