Plecos are nocturnal fish. They spend most of their day resting inside caves, overhangs, deep burrows, or dark crevices of the tank. They come out at night to search for food at the tank’s bottom. Plecos are solitary, shy fish that like to spend their day in the dark corners of the aquarium.
Let’s now understand why plecos are considered nocturnal in more detail.
Why Are Plecos Considered Nocturnal?
Fish are considered diurnal or nocturnal depending on the time of the day they’re active.
The term “nocturnal” refers to species that prefer to be active at night.
Plecos are naturally nocturnal and exhibit many physical and behavioral characteristics that match other nocturnal fish species.
Given below are the main reasons why plecos are considered nocturnal.
1. Active At Night
Plecos are primarily active in the morning and evening hours.
This typical behavior leads to the conclusion that pleco fish are nocturnal.
During the day, plecos typically rest inside the cave structures or are found hiding near the plants or driftwood.
2. Slow Swimmers
Most nocturnal species, including plecos, are slow swimmers than diurnal fish.
Nocturnal fish aren’t able to swim fast simply because of their reduced visibility.
3. Large Eyes
The eyes of nocturnal fish are bigger than diurnal fish of similar body size.
Large eyes help them to better adapt to a light-deficient environment.
Like other nocturnal creatures, plecos also tend to have big eyes to see better in low-light conditions.
4. Dark Colors
Nocturnal fish often have dark colors like red or brown.
These colors get absorbed by water and are the first colors of the spectrum to become indistinct as light intensity drops.
Dark colors easily camouflage in the surroundings making it easier for the fish to hide from predators during the day.
Another characteristic of plecos, like other nocturnal fish, is that they tend to be solitary.
On the other hand, many diurnal species are social and live in large schools.
6. Shy Behavior
Plecos are often shy and hide in caves or under overhangs during the day.
They move through the vegetation inside the tank to remain invisible.
Most nocturnal fish prefer to stay hidden in the dark corners of the aquarium. These fish are timid and hard to catch.
7. Well-Developed Lateral Line
All fish have some lateral line.
However, nocturnal fish have a well-developed lateral line or sensory system that helps them detect water movements, vibrations, and pressure gradients.
A well-developed lateral line also assists them in finding prey in the dark or low light conditions.
How To Setup Aquarium For Nocturnal Plecos?
Plecos belong to the freshwaters of South America. They prefer fast-moving rivers with rocks and pebbles at the bottom.
To make plecos comfortable, create an environment that replicates their natural habitat.
Given below are the essential things that you must have in the tank for nocturnal plecos.
1. Traditional Riverbed Substrate
Plecos live at the bottom of an aquarium and enjoy burrowing in the sand at night.
Use gravel, stones, and clay to replicate their natural habitat so that your pleco can engage itself in digging burrows at the tank’s bottom.
2. Filtration System
Plecos are known to clean the tank by eating algae. At the same time, they create a lot of waste, impacting the water quality.
So installing a robust filtration system can efficiently eliminate toxins and improve water quality.
The filter will also create the necessary gas exchange and water circulation to aerate the tank.
3. Moving Water
Plecos are found primarily in freshwater rivers and streams.
They prefer fast-flowing rivers with rocky bottoms. So you must provide a similar environment to make them feel at home.
You can use a strong filter, air stone, or air pump to create water movement inside the tank.
This will help the plecos swim freely and help maintain water quality.
Ensure that the aquarium lights are dimmed so that they don’t disturb the plecos.
You should keep lighting to a minimum and no more than seven to ten hours per day.
At night, you should switch the lights off. However, you can use a red light at night to see if plecos are active.
5. Hiding Places
To set up an aquarium for the nocturnal plecos, you must create a habitat with many hiding spots.
Caves, castles, and shipwrecks are great hiding spots for the plecos.
Most plecos love to feed and rest on driftwood too. So add some of these decorations to the tank.
6. Live Plants
Plecos create a lot of bio-load inside the tank.
So live plants will help increase the oxygen levels of the water and provide the required cover for the fish to rest.
Live plants will also act as a food source for the plecos.
However, plecos are known to tear down plants from the substrate.
So choose hardy, deep-rooted plants like Amazon Swords, Anubias, and Java Fern.
7. Water Siphon
Nocturnal fish grow large and create a lot of waste.
A water change can’t eliminate all the waste and pathogens from the aquarium.
So a gravel vacuum is helpful to dispense the water from the tank. It also makes cleaning gravel easy and efficient.
Besides replicating their natural habitat, it’s also vital to provide proper care to the plecos.
With regular maintenance and a well-balanced diet, you can improve the longevity of your pleco fish.
Are Bristlenose Plecos Nocturnal?
Bristlenose plecos are nocturnal bottom-dwelling catfish. They prefer to come out to feed and explore the surroundings at night.
Bristlenose plecos spend their day relaxing and hiding in dark caves and hiding spots.
Their camouflaging colors make it difficult to spot them during the day.
Are Gold Nugget Plecos Nocturnal?
Gold nugget plecos are nocturnal species that avoid areas where there’s light.
They hide under the rocks or caves during the day and wait for the noise and light to diminish.
At night, they come out of their hiding place in search of food at the tank’s bottom.
Are Snowball Plecos Nocturnal?
Yes, snowball plecos are nocturnal. They come out during the night, flashing their white or yellow snowballs in the dark.
They feed on algae and decaying food at night.
During the day, they nestle in the plants and caves but can be seen moving through the heavily planted tank.
Are Blue-Eyed Plecos Nocturnal?
Yes, blue-eyed plecos are nocturnal. They’re one of the rarest plecos found in the aquarium hobby.
They spend their day resting in the dark crevices.
These plecos are active at night and require a lot of space to swim and move around.