A guide to why shrimps seem to change colour.
So, you just discovered your shrimp are a new variety of chameleon shrimp? You put a red one in the tank and now there are only white ones? You bought a blue one that was a rich blue and now it has faded? Perhaps you had one that completely changed colour – from white to green?
Here are some top reasons why people have found their shrimp have changed colour.
1) Stress that causes coloured shrimp to become white or very pale.
Shrimp are like tropical fish. I had a bright blue and red cardinal fish once – well it was in the aquatic shop. When I got home the fish in then bag were white and looked a different shape!! I even made the newbie error of phoning up and asking what to do as I’d been given the wrong fish. I swear they looked completely different.
Well, I learnt something that day and felt very stupid. Stressed fish and shrimp can lose their colour within minutes. This can even change the shape we perceive them to be. My white fish soon changed back to the normal colour. Shrimp will do the same – and may also shed their skin (so you see the skin and think they died!!). Give them a few days (or even 24 hrs) and they should perk up.
2) Sick shrimp that turn opaque
Shrimp that start clear and turn opaque are usually ill from a bacterial or fungal infection.
3) Shrimp that turn green or blue when they were transparent.
Shrimp with full or partial segments that are transparent will show the colours of their inside organs. If they have eaten coloured food – then this can show through and a clear segment can turn bright green or blue!!
4) Shrimp that have been fed a colour dye.
Similar to the above, some crooks take clear shrimp, feed them colourings so they turn slightly blue/green/yellow or red … and sell them as shrimp of this colour. They are thus fake varieties and it is very wrong (so choose shrimp from reputable people). The duped person gets them home, they eat normal food, their bodies clean up and become their normal transparent/white colour.
5) Lighting on an aquarium (or reflection from coloured ornaments/plants)
Certain lights can change how the human eye perceives the colour of things in the tank. Some lights make plants look greener or shrimp look brighter. Change the light and they appear to have changed!
6) Age – older shrimps gain brighter colours
Shrimps will naturally get larger colour segments and brighter colours as they age – which can be enhanced by a good diet and optimum conditions.
7) Red ornaments and plants make duller red shrimps.
Shrimp appear brighter and colour up better on a contrasting background. This is why most people choose black substrate, dark wood and green plants.
8) Food options
Some foods and nutrients will keep a shrimp in good colour – I’ve never personally tested different types of foods and how much this is true – but it makes sense that good nutrition gives good coloured healthy shrimps.