This article will explore cold water algae eaters, usually prey for larger predators, but they have a few secret weapons that allow them to escape from danger.
Their most recognisable defence is their ability to change colours and patterns in the cold and warm waters.
A skill will enable them to blend in with the environment and make high profile predators like sharks easier targets.
The cold-water fish has an interesting life cycle. It starts off life looking like a tiny crustacean called “nauplius” before developing into a larva or juvenile stage that resembles small shrimp-like creatures.
The final stage of cold water algae eater’s life is when they become adults swimming around cold waters close to the surface of the ocean floor.
What cold water algae eaters are
Coldwater Algae Eaters are a family of fish that lives in the cold water and eat algae.
They typically have a long snout, small teeth, microscopic scales, and sometimes live in schools. Many people keep them in community aquariums (also called “fishbowls”)
Most coldwater algae eaters live at around 50 degrees Fahrenheit, but some areas deep as 80 to 95 degrees.
The deeper they live, the warmer their water is. However, a theoretical line exists for these fish where their living conditions become life-threatening if the temperature rises above 65 degrees.
In fact, in the wild, if this temperature threshold is breached for a long enough period of time (hundreds of years), it causes mass extinctions in them.
This line does not exist for all coldwater fish, nor does it refer to temperature changes overnight but instead refers to an average change over time.
Despite this, algae eaters are resilient and adaptable (another reason they live in cold water).
They have been found in the Great Lakes, where it is common to have substantial temperature changes from day to night, even more than 65 degrees.
This change has shaped them into a much different fish from their tropical cousins, but they retain some of all fish’ essential characteristics.
How cold water algae eaters change colour to hide in their environment
Coldwater algae eaters change colour to hide in their environment.
If they are surrounded by red or brown algae, the cold water algae eater is a pinkish-brown colour, but it is a brownish-green colour if green algae surround them.
They have evolved this camouflage to protect themselves from predators.
It is like an art project, and the algae are their paint.
Coldwater algae eaters are also known as sand sifters or sand shrimp.
They have tiny pincers that they use for moving lots of small pieces of sand around.
The bits of sand make up their food supply.
They will often eat the green parts off living green algae if they can catch it.
Sometimes the cold water algae eaters even eat dead plants that have washed up onshore.
Coldwater algae eaters live at depths of 300 to 500 feet below the surface.
They need lots of oxygen and do not like high temperatures, so they stay in deeper waters.
They will burrow into the sand and then camouflage themselves.
The eyes of the cold water algae eater are located on top of their head so they can see danger coming from any direction.
They also have strong antennae at the front of their heads to feel for food and smell odours in the water.
Their bodies are covered with tiny hairs that help them sense vibrations in the water.
The cold water algae eaters have a large pair of feathery fins for swimming and moving about in their environment.
They swim near the bottom of the ocean, which is where all the interesting bits are.
The egg cases (spawn) often wash up on the shore at different times of the year, depending on where you are.
The cold water fish’s life cycle and what it looks like at each stage
Coldwater fish spend most of their day near the surface of the water.
They only go deeper to feed and to find mates.
The eggs of cold water fish are sticky, meaning that they can attach to plants near the water’s surface or stay afloat for a few days.
They have a long life cycle, which goes through stages called larval and juvenile.
Larvae develop into juveniles in about six months.
Young cold water fish live near the water’s surface, while adult fish live in deep ocean waters.
Cold Water Fish: Physical Characteristics & Behavior
Oceanic fish have special physical characteristics that help them swim and survive in low oxygen conditions found at great depths.
They contain a gas-filled swim bladder that helps them control their buoyancy, which they need to move up and down in the water column.
Some species of cold-water fish have a layer of fat under their skin for insulation.
This heat-retention ability is needed since there is no sunlight at such great depths.
Why cold water algae eaters are so special
Coldwater algae eaters are so special because they require cold water.
They can usually be found in the northern hemisphere in places like Japan and Norway.
Such cold water algae eaters live at a depth of up to 50 meters below the ocean’s surface.
Their food is composed of the species Chrysochromulina polylepis and Nitzschia laevis.
Coldwater algae eaters are essential because they consume plankton that could otherwise damage ocean life if it passes upward and reaches the water’s surface.
Depletion of this species has led to an increase in the number of zooplankton and other organisms that cause ocean surface discolouration.
Most importantly, they are an essential element in the ecosystem.
They help keep the temperature down in the depths of the ocean by consuming food sources at levels near where thermal neutral zones begin.
Coldwater algae eaters are also a source for pigments used as colourants in commercial cosmetics.
These creatures can have body lengths 15-20 cm long, with two lateral fins extending vertically from head to tail on both sides of their body.
Their eyes are located on top of their heads, indicating vision is not essential for this species; however, it is known that cold water algae eaters do use echolocation.
Their bodies are covered with large scales instead of tiny scales like other fish. Because larger scales cover their bodies, this prevents them from dealing with the air-sea interface; therefore, they don’t have to worry about air drying out or saltwater drying out their skin.
This means that cold water algae eaters can remain active and healthy in their habitat for a long time.
Conclusion
Coldwater fish are unique because they live in cold waters and can change colour.
They have a life cycle that starts with eggs and ends with death, anywhere from 1-4 years old.
The best part is seeing the beauty of these fish as they transform throughout each stage of their lives.
Many people don’t know much about this type of fish or how it changes colours; hopefully, after reading this article, you will!
If you’re interested in purchasing one for your aquarium, check out our blog post on “What Tank Size Do I Need For My Fish?”
We hope that you enjoyed learning more about cold water algae eaters today!
