Skip to Content

Do Plecos Sleep? (A Few Must-Know Facts)

Disclosure: When you purchase something through my affiliate links, I earn a small commission. As an Amazon Associate, I earn from qualifying purchases.

Since Plecos are primarily inactive during the day, it’s hard to tell if they are suffering or simply sleeping. In any case, Plecos often rest motionlessly in a sheltered area.

But do Plecos actually sleep, and if they do, how can we tell if they are sleeping or if they are sick?

How can we encourage healthy sleep patterns in Plecos, and what should we do if the fish sleeps excessively?

In this article, I will address these questions and more, so you leave with all the information you need. Let’s get started.

Do Pleco Fish Sleep?

Yes, Pleco fish do sleep. However, their sleeping patterns differ from ours and may not always be obvious to the casual observer.

  • When Plecos Sleep: Plecos are primarily nocturnal, meaning they are most active during the night. So, daytime is often their resting phase.
  • How Long They Sleep: On average, Plecos can rest or sleep for several hours during the day. However, exact durations vary based on individual needs and environment.
  • Typical Resting Spots: Plecos love to nestle under rocks, inside caves, or against aquarium decorations. These hiding spots offer them a sense of security and darkness ideal for resting.
  • Signs of a Sleeping Pleco: A resting Pleco will be stationary, often nestled in one of its favorite spots, with minimal fin movement. While they might react to disturbances, they generally remain calm and relaxed.

Also Read: Pleco Fish Facts

How Long Do Plecos Sleep?

Plecos generally rest or sleep for several hours during the day, given their nocturnal nature. The exact duration can vary, but typically, they’ll rest for about 6-8 hours daily.

  • Natural Behavior: Plecos are adapted to be more active at night. Thus, daytime becomes their primary period of rest.
  • Varying Durations: While 6-8 hours is typical, some Plecos might rest for shorter or slightly longer durations based on health and environmental factors.
  • Activity Cycles: It’s not uncommon for Plecos to have short periods of activity even during their rest hours, especially if there’s a disturbance or a food source available.

How Can You Determine If Your Pleco Fish Is Sleeping?

Identifying a sleeping Pleco might be a bit tricky since they can stay quite still even when awake. However, certain signs and behaviors indicate that they’re in a restful state.

  • Stationary Posture: A resting Pleco tends to remain fixed in one spot, with minimal to no movement of its fins.
  • Diminished Responsiveness: If a Pleco is sleeping, it might not respond immediately to tank disturbances or sudden lights.
  • Position in the Tank: Plecos that are resting often position themselves in their preferred resting spots, away from active tank mates.
  • Relaxed Appearance: Unlike their alert state, sleeping Plecos have a more relaxed posture, with no rapid breathing or fin activity.

Also Read: Do Plecos Bite?

Typical Resting Spots for Pleco Fish

Plecos have a natural instinct to find secure and cozy spots for their rest periods. Given the choice, they have some clear favorites in the tank.

  • Underneath Rocks: Plecos often choose the underside of rocks as a resting place, which offers them security and shade.
  • Inside Caves: Many aquarists provide caves in Pleco tanks, and these become prime resting spots due to their dark and enclosed nature.
  • Behind Plants: Dense plant areas in the tank can be ideal for Plecos to hide and rest, giving them a sense of safety from predators.
  • Against Decorations: Items like driftwood or other large aquarium decorations are often chosen by Plecos as resting spots because of their structure and shade.

Distinguishing Between Resting and Health Issues in Your Pleco Fish

While it’s natural for Plecos to rest, prolonged inactivity or certain behaviors can hint at potential health problems.

It’s essential to recognize these signs early to ensure the well-being of your Pleco.

  • Duration of Inactivity: While Plecos rest for several hours, continuous inactivity spanning days might be a sign of health concerns.
  • Physical Symptoms: Healthy resting Plecos don’t show physical anomalies. However, spots, discoloration, or lesions might indicate illness.
  • Erratic Behavior: If a Pleco is darting around the tank suddenly or floating upside-down, it’s not just resting; it might be distressed or sick.
  • Loss of Appetite: Plecos generally have a good appetite. Consistent refusal of food, even during active hours, can signal health issues.
  • Breathing Patterns: A resting Pleco breathes slowly and steadily. Rapid or labored breathing can be a clear sign of distress or underlying health problems.

Also Read: Why Is My Pleco Not Moving?

What Should You Do If Your Pleco Fish Sleeps Excessively?

If you find your Pleco sleeping more than 6-8 hours a day, there are a few steps you should take:

1. Review Tank Temperature Settings

For the health and well-being of Plecos, maintaining an appropriate temperature is essential.

  • Ideal Temperature Range: Specifically, Plecos need temperatures between 72°F to 86°F (22°C to 30°C). Outside this, they might become inactive or sleep more.
  • Gradual Adjustments: For instance, if it’s 70°F, don’t raise to 80°F immediately. Aim for 1-2°F change per day to minimize stress.
  • Heater Check: Regularly inspect heaters for signs of malfunction like inconsistent heating or visible damage.
  • Regular Monitoring: Using digital thermometers provides accurate readings; check twice daily, morning and evening, for consistency.

Also Read: Plecos Temperature Guide

2. Investigate Potential Presence of Toxins

Plecos, being sensitive creatures, can be affected by toxins that disrupt their regular activities.

  • Regular Water Tests: Kits like API Freshwater Master Test Kit (link to Amazon) can identify toxin levels, ideally testing every two weeks.
  • Identifying Toxins: Common culprits include ammonia, nitrites, and high nitrates. Plecos exposed might appear sluggish or sleep more.
  • Water Changes: If toxins are detected, change 30-50% of tank water. Use dechlorinated water to ensure safety for Plecos.
  • Avoid Overcleaning: While cleanliness is key, overcleaning can strip beneficial bacteria. Aim for a balance.

3. Ensure Adequate Oxygenation in the Tank

Plecos require oxygen-rich water to thrive and remain active.

  • Aeration Techniques: Utilizing air stones or bubble wands can enhance oxygen levels, vital for Plecos’ respiratory processes. I personally installed the Hygger Aquarium Air Stone (link to Amazon).
  • Signs of Low Oxygen: Plecos gasping at the surface or reduced movement indicate oxygen deficiencies and increased sleep.
  • Plant Consideration: Live plants like Anubias or Java Fern can naturally oxygenate water, benefiting Plecos.
  • Water Flow: Ensure filters circulate water efficiently. For instance, a 50-gallon tank needs a filter with a flow rate of 200-250 gallons per hour for optimal oxygenation.

Also Read: Do Plecos Need A Bubbler?

4. Be Mindful of Tank Mates and Aggression

Peaceful cohabitation is essential for Plecos to avoid stress and ensure they rest properly without excessive sleeping.

  • Compatible Mates: Fish like Tetras or Corydoras are peaceful and work well with Plecos. Avoid aggressive species like Cichlids.
  • Observe Behavior: Watch for nipped fins or chasing. For example, if a Pleco is constantly cornered, it may sleep excessively as a stress response.
  • Tank Territories: Introduce cave-like decorations or driftwood. Plecos are territorial; having their own space reduces conflicts.
  • Introducing New Fish: When adding new tank mates, it’s advisable to rearrange decor. This action resets territories, preventing immediate aggression towards Plecos.

Also Read: Pleco Fish Tank Mates

5. Seek Advice from Experienced Fish Keepers or Online Forums

The aquarium community is vast, and many enthusiasts have experienced similar Pleco concerns.

  • Specific Queries: For instance, if your Pleco sleeps after feeding, ask if this is normal behavior or related to a dietary issue.
  • Reputable Forums: Platforms like AquariumAdvice or Fishlore have seasoned aquarists who can provide insights specific to Plecos.
  • Local Aquarium Clubs: Joining such clubs can be beneficial. For example, meetings might offer talks on Pleco behavior, health, or best care practices.
  • Document Changes: When seeking advice, note changes in your Pleco’s behavior or environment. Details like “Pleco began sleeping excessively two weeks after introducing a new plant” can provide crucial context for accurate guidance.

Promoting a Good Night’s Sleep for Your Pleco Fish

Here’s how you can promote healthy sleeping patterns among your Pleco fish:

1. Invest in Suitable Plants or Decor for Natural Shelter

Plecos relish hideaways, mirroring their wild habitats, giving them both security and comfort.

  • Natural Choices: For instance, Java moss is great because Plecos won’t typically eat it, and it grows well in varied conditions.
  • Decor Options: Driftwood, besides being aesthetic, allows Plecos to graze on biofilm. A 15-inch piece suits a 20-gallon tank.
  • Size Matters: If you have a 5-inch Pleco, ensure caves or hideaways are at least 6 inches in length for comfort.
  • Placement: Distribute hiding spots evenly. In a 40-gallon tank, 2-3 strategically placed shelters reduce territorial disputes among Plecos.

Also Read: Plants Plecos Love

2. Use Dim or Ambient Lighting During Evening Hours

Plecos are more active during low-light periods, so simulating dusk can promote natural behaviors and rest.

  • Dimming Tools: Consider LED lights with dimming features. For a 24-inch tank, a 20W dimmable LED light can suffice. My recommendation: Hygger Aquarium LED Light (link to Amazon).
  • Natural Dusk Simulation: Some advanced lights have timers to gradually dim, mimicking sunset, beneficial for Plecos.
  • Blue Lighting: A popular choice for evening. It’s dim enough for Plecos yet allows owners to observe fish activity.
  • Lighting Duration: Typically, 8-10 hours of light suffices. For Plecos, 6-8 hours of dimmed light post daylight is ideal.

Also Read: Do Plecos Need Light?

3. Avoid Overfeeding Which Can Cause Lethargy

Overfeeding not only affects water quality but can make Plecos lethargic and prone to excessive sleep.

  • Pellet Count: For medium-sized Plecos, feeding 2-3 sinking pellets daily is adequate, ensuring they’re consumed within 5 minutes.
  • Vegetable Intake: Offer greens like zucchini slices twice a week. A 2-inch slice is sufficient for a 5-inch Pleco.
  • Feeding Schedule: Feed Plecos in the evening, aligning with their natural nocturnal habits, ensuring active digestion.
  • Monitor Consumption: If food remains after 10 minutes, it’s excessive. Adjust quantities to prevent Pleco lethargy.

Also Read: How To Feed Plecos

4. Regularly Clean the Tank to Prevent Ammonia Build-up

Ammonia spikes can lead to stressed and lethargic Plecos. Regular cleaning mitigates this risk, ensuring your Pleco’s health.

  • Testing Kits: For Plecos, maintaining an ammonia level of 0 ppm is essential.
  • Water Change Routine: Weekly, change 25-30% of water. In a 40-gallon tank, that means replacing around 10-12 gallons.
  • Substrate Cleaning: Use gravel vacuums. For a tank with a 30-inch base, a 2-inch diameter siphon cleans effectively without disturbing Plecos.
  • Filter Maintenance: Rinse filter media monthly in tank water. If you have a 300 GPH filter, clean every 3-4 weeks for best performance.

5. Monitor and Control Water Flow for Optimal Comfort

Plecos are accustomed to steady currents. Proper water flow mimics this environment, preventing them from feeling stressed or overly lethargic.

  • Filter Choice: For a 50-gallon tank, a filter with 200-250 GPH (Gallons Per Hour) ensures sufficient flow without being overpowering for Plecos.
  • Water Movement Signs: Observe plants or decorations. Gentle, consistent swaying indicates a pleasant flow for your Pleco.
  • Positioning: Place the filter output towards the tank’s side, not directly on Plecos, for a more diffused and comfortable flow.
  • Powerheads: If needed, add them to enhance circulation. In a 60-gallon tank, a 500 GPH powerhead at the opposite end from the filter can evenly distribute flow, benefiting Plecos.

Also Read: Can Plecos Live Alone?


For quick readers, here’s a short recap:

  • Plecos are nocturnal, resting mainly during the day in spots like caves or under rocks.
  • Distinguishing between resting and health issues in Plecos is vital; watch for prolonged inactivity or erratic behaviors.
  • For excessive sleep, check tank temperature, toxins, oxygen levels, tank mate behavior, and seek expert advice.
  • Enhance Pleco sleep by providing shelters, using dim evening lighting, feeding appropriately, and ensuring clean water.
  • Overall Pleco care aims to mimic their natural habitat for their comfort and health.