Do you ever notice your gourami acting differently after you clean its tank? Many owners report subtle changes in behavior that may seem unusual. These small fish can react to shifts in their environment.
Gouramis can experience temporary stress or disorientation after tank cleaning. Changes in water flow, rearranged decorations, or altered scents can make them feel displaced, but these effects are usually short-term and manageable with proper care.
Observing your fish closely after cleaning helps you understand their adjustment process and maintain a calm, stable environment for long-term well-being.
How Tank Cleaning Affects Gourami Behavior
Tank cleaning can be a stressful event for gouramis. These fish are highly sensitive to changes in their environment. Rearranging plants, decorations, or substrate alters familiar landmarks they use to navigate. Even small changes in water flow or temperature can cause temporary confusion. Gouramis may hide more than usual, swim erratically, or show reduced activity. Observing these behaviors closely can help you understand their adjustment period. Providing hiding spots and maintaining consistent water conditions minimizes stress. Regular, gentle cleaning routines prevent sudden shocks and allow the fish to adapt gradually. Water chemistry plays a key role; sudden shifts in pH, hardness, or temperature can intensify stress responses. Paying attention to these details ensures your gourami stays healthy and comfortable. Over time, most gouramis quickly regain normal behavior, but awareness of their sensitivity helps maintain long-term well-being and a stable environment for them.
Stress after cleaning is usually short-lived and manageable with steady care.
Gouramis rely on visual and chemical cues to feel secure. When their surroundings change, they may take hours or days to recognize landmarks again. Gradually reintroducing familiar decorations and avoiding sudden changes supports their comfort. Feeding them consistently and observing behavior ensures they adapt smoothly, maintaining health.
Signs Your Gourami Feels Displaced
Hiding frequently or avoiding the main swimming area indicates unease.
Erratic swimming, reduced appetite, and lingering near tank edges are common signs. Some gouramis may flare their fins or pace along glass surfaces. These behaviors usually subside as they readjust. Keeping decorations consistent and providing gentle water movement helps them regain confidence. Monitoring interactions between gouramis is also important, as stress can increase territorial behaviors. Adjusting lighting gradually and avoiding sudden noises further reduces discomfort. Over time, attention to water quality, tank layout, and routine care ensures the fish feel secure. Observing their unique responses allows you to create a supportive environment. By recognizing these signals early, owners can intervene to minimize stress and maintain a balanced habitat for all tank inhabitants. Proper planning and small adjustments lead to healthier, more confident gouramis that thrive even after cleaning routines.
Preventing Stress During Tank Cleaning
Maintaining stable water conditions is key. Gradual changes, gentle cleaning methods, and consistent routines help gouramis stay calm. Avoid complete water replacement and sudden rearrangements, as these can trigger stress responses and disorientation in your fish.
Using a partial water change rather than a full one preserves beneficial bacteria that gouramis rely on. Cleaning decorations and substrate carefully avoids stirring up debris that could cloud water or release toxins. Introducing new plants slowly or in familiar areas allows the fish to explore without anxiety. Monitoring water parameters before and after cleaning ensures that temperature, pH, and hardness remain stable. Providing hiding spots and consistent lighting during and after cleaning helps gouramis feel secure. Over time, these careful practices reduce stress and promote regular behavior patterns, making each tank cleaning less disruptive for your fish.
Regular observation after cleaning is essential. Watch for changes in swimming patterns, appetite, or social behavior. If stress signs persist, minor adjustments can help gouramis readjust faster and maintain overall health.
Adjusting the Tank Environment for Comfort
Reorganizing the tank gradually improves adaptation. Placing decorations in familiar positions and maintaining visual landmarks supports confidence.
Water flow and filtration adjustments should be subtle. Too strong a current can overwhelm gouramis, especially after cleaning. Using gentle flow or redirecting currents toward less populated areas reduces stress. Light intensity and duration should remain consistent to prevent disorientation. Observing how gouramis interact with new placements reveals preferences and helps optimize the tank layout. Feeding schedules also contribute to comfort. Keeping food accessible and providing hiding spots near feeding areas encourages normal behavior. Small changes over time ensure a stable, supportive environment, allowing gouramis to thrive while minimizing displacement effects.
Monitoring Behavior After Cleaning
Observe your gourami’s movements closely. Changes in swimming, hiding, or feeding patterns indicate how well they are adjusting to the cleaned environment.
Note interactions with other fish. Increased aggression or withdrawal may signal temporary stress. Small adjustments can help them regain comfort quickly.
Feeding and Routine Maintenance
Maintaining a consistent feeding schedule supports stability. Avoid overfeeding, as sudden dietary changes can worsen stress. Regularly check water quality, ensuring temperature, pH, and hardness remain stable. Clean filters gently to preserve beneficial bacteria, and limit sudden rearrangements. Consistency in care helps gouramis feel secure and adapt faster after cleaning.
Recognizing Signs of Long-Term Stress
Persistent hiding, loss of appetite, or unusual aggression may indicate prolonged stress. Monitoring these behaviors early allows timely intervention and prevents health issues.
FAQ
Can a gourami get stressed from a full water change?
Yes, a full water change can be stressful. Gouramis rely on stable water parameters and familiar scents. Sudden shifts in temperature, pH, or water chemistry can disorient them. Partial water changes are safer, maintaining beneficial bacteria while reducing the chances of stress.
How long does it take for a gourami to adjust after cleaning?
Adjustment usually takes a few hours to a couple of days. Factors like tank size, complexity of decorations, and the individual fish’s temperament affect the timeline. Providing hiding spots and consistent conditions helps gouramis regain comfort faster. Monitoring behavior during this period is important.
Why does my gourami hide more after tank maintenance?
Hiding is a natural response to environmental change. When decorations are moved or water is altered, gouramis feel less secure. Hiding allows them to reduce stress until they recognize landmarks and reestablish territory within the tank. Gradual changes minimize this behavior.
Can rearranging tank decorations affect gourami behavior?
Yes, gouramis use visual and chemical cues to navigate. Moving decorations or plants disrupts familiar patterns, causing temporary confusion or stress. Keeping some consistent landmarks and gradually introducing new elements supports smoother adjustment.
Is it normal for gouramis to eat less after cleaning?
Reduced appetite can occur when they feel unsettled. This is usually temporary. Maintaining consistent feeding times and providing safe, easily accessible areas encourages them to resume normal eating patterns. Avoid overfeeding, as stress combined with excess food can harm water quality.
Do gouramis react differently to tank cleaning based on their age?
Younger gouramis may adapt more quickly because they are still exploring their environment. Older or more established fish can be more territorial and sensitive, making them prone to hiding or cautious behavior after significant changes. Awareness of these differences helps tailor care routines.
How can I reduce stress during regular maintenance?
Perform partial water changes, avoid moving all decorations at once, and clean filters gently. Keep water parameters consistent and provide hiding spots. Maintaining a predictable routine, including feeding times and lighting, helps gouramis feel secure. Gradual changes minimize stress responses.
Can stress from cleaning cause long-term health issues?
Prolonged or repeated stress can weaken the immune system, making gouramis more susceptible to disease. Regular observation, stable water quality, and careful tank management prevent long-term problems. Intervening early if abnormal behaviors persist ensures the fish remains healthy.
Should I separate gouramis during cleaning?
Separation is generally unnecessary unless you have aggressive species or individuals prone to stress. Most gouramis tolerate cleaning when changes are gradual. Focus on maintaining calm water flow and stable conditions to reduce the risk of displacement.
How do I know if my gourami is fully comfortable again?
Normal swimming patterns, consistent feeding, and regular interaction with tank features indicate comfort. Reduced hiding, exploring familiar areas, and relaxed movements show that the gourami has readjusted. Observing these signs over several days confirms successful adaptation.
Can tank lighting affect a gourami’s adjustment after cleaning?
Yes, abrupt changes in lighting can add to stress. Gradually increasing or maintaining consistent light levels helps them feel secure. Avoid sudden bright flashes or extended dark periods, which can disorient or scare them.
Is it helpful to add new plants immediately after cleaning?
Adding plants slowly is best. Sudden additions can overwhelm gouramis, especially after a recent change. Introduce new decorations gradually and in familiar areas so fish can explore safely without feeling displaced.
Can multiple gouramis influence each other’s stress levels?
Yes, gouramis can sense the stress of tank mates. Aggression or hiding in one fish may trigger similar behavior in others. Maintaining enough space, providing multiple hiding spots, and monitoring interactions reduces stress spread within the tank.
Do gouramis remember tank layouts?
Gouramis form spatial memories of their environment. Familiar landmarks, hiding spots, and swimming paths provide security. Changing these suddenly can cause temporary disorientation, while gradual adjustments allow them to update their memory with minimal stress.
What signs indicate serious stress needing action?
Persistent hiding, refusal to eat, rapid breathing, or unusual aggression are warning signs. If these behaviors continue beyond a couple of days, reviewing water quality, tank layout, and health is necessary. Intervention ensures long-term well-being and prevents disease or injury.
How often should tank cleaning occur to minimize stress?
Moderate, consistent cleaning every one to two weeks is ideal. Frequent, abrupt maintenance can cause repeated stress. Partial water changes and careful decoration management maintain water quality while keeping the gouramis comfortable and secure.
Are some gourami species more sensitive than others?
Yes, species like the dwarf gourami are more easily stressed by environmental changes, while larger gouramis may be more resilient. Understanding species-specific sensitivity helps in planning cleaning routines and tank management effectively.
Does water temperature affect post-cleaning stress?
Sudden temperature changes can increase stress. Maintaining stable water temperature during cleaning prevents disorientation and supports metabolic stability. Using a thermometer and matching replacement water carefully avoids shock.
Can adding hiding spots reduce post-cleaning anxiety?
Providing shelters, plants, or caves helps gouramis feel safe after tank changes. Hiding spots offer security while they adapt to new layouts, reducing stress-related behaviors and encouraging normal activity sooner.
How long should I monitor my gourami after cleaning?
Observe closely for at least 48 hours. Look for changes in swimming, eating, and interaction with tank mates. Early detection of stress allows for adjustments in care, water conditions, or environment to ensure comfort and health.
Do gouramis recognize their owners after tank changes?
Yes, they can recognize familiar humans, but stress may temporarily make them shy or withdrawn. Regular, calm interaction and feeding routines reinforce trust and help them feel safe even after environmental disruptions.
Can water movement cause stress after cleaning?
Strong currents can overwhelm gouramis, especially after changes. Adjusting flow gradually or redirecting currents to less populated areas prevents fatigue and reduces anxiety, helping them explore the tank confidently.
Is it necessary to check water parameters immediately after cleaning?
Yes, testing for pH, ammonia, nitrite, and temperature ensures stability. Small fluctuations can affect behavior, so prompt monitoring allows corrections to prevent unnecessary stress or long-term health issues.
What is the best approach to maintain a calm tank environment?
Consistent routines, stable water conditions, gradual changes, and adequate hiding spaces create a secure environment. Observing behavior daily and making small, incremental adjustments ensures gouramis remain comfortable and healthy after every cleaning session.
How do I help gouramis readjust after rearranging decorations?
Return some familiar landmarks and avoid moving multiple decorations at once. Allow time for exploration and limit sudden interactions. Gentle water movement and consistent lighting make adaptation smoother, encouraging normal behavior to return faster.
Can stress affect breeding behavior in gouramis?
Yes, stress from tank cleaning or environmental changes can temporarily suppress breeding. Maintaining stable conditions, hiding spots, and a calm atmosphere supports reproductive behavior once the fish feel secure again.
Do gouramis show signs of relief after adjustment?
Yes, resumed feeding, relaxed swimming, and exploring familiar areas indicate recovery. Reduced hiding, normal social interactions, and consistent activity demonstrate that they have regained comfort and feel safe in their environment.
Can frequent tank rearrangements harm long-term behavior?
Repeated, sudden changes can cause chronic stress, reducing appetite, increasing aggression, or weakening immunity. Limiting rearrangements and maintaining familiar landmarks supports stable behavior and long-term health.
Are certain water treatments helpful post-cleaning?
Adding stress-reducing water conditioners or bacterial supplements can support recovery, especially after larger changes. These treatments stabilize water chemistry, reduce toxins, and promote a healthy environment for gouramis to adjust safely.
Do gouramis prefer the same spot after cleaning?
Yes, they often return to familiar areas. Recognizing and maintaining these preferred spots helps them feel secure, even after partial tank changes or minor rearrangements. Observing preferences allows careful planning of tank layout.
Can stress make gouramis more aggressive?
Yes, stress can increase territorial behavior. Maintaining sufficient space, hiding areas, and stable conditions reduces aggression, preventing conflicts and supporting a harmonious tank environment.
How important is gradual feeding after cleaning?
Gradual, consistent feeding encourages normal appetite and reduces stress. Avoid sudden changes in food type or quantity, as this can exacerbate discomfort or disorientation, helping gouramis regain their usual routine safely.
Do gouramis react to noises during cleaning?
Yes, loud or sudden noises can startle them, adding to stress. Gentle handling, minimal disruption, and calm movement around the tank reduce anxiety during maintenance activities.
Can adding companions reduce stress?
Not necessarily. Introducing new fish immediately after cleaning may increase anxiety. Stability is more important than adding companions. Wait until the tank environment is secure and gouramis show normal behavior before introducing any new individuals.
Is it helpful to observe gouramis at night after cleaning?
Yes, nocturnal behavior can reveal lingering stress. Watching movement and hiding patterns at night ensures they feel secure around the clock and highlights areas of the tank that may need adjustments.
How can I support a shy gourami post-cleaning?
Provide extra hiding spots, maintain gentle water flow, and feed in accessible areas. Minimizing disturbances while keeping conditions stable encourages the fish to explore and regain confidence gradually.
Does tank size influence adjustment speed?
Larger tanks provide more hiding spots and swimming space, reducing stress, while smaller tanks can feel more confining, making changes more noticeable. Proper layout and gradual adjustments help regardless of size.
Are gouramis more stressed during seasonal temperature changes?
Yes, temperature fluctuations can add stress, especially after cleaning. Monitoring and maintaining stable conditions during seasonal changes supports comfort and reduces the likelihood of disorientation or behavioral changes.
Can adding floating plants help after cleaning?
Yes, floating plants offer cover and diffuse light, helping gouramis feel safe. They provide visual boundaries and a sense of security, reducing stress and encouraging normal swimming and exploration behaviors.
How can I tell if my gourami is still stressed?
Signs include hiding, erratic swimming, reduced feeding, or aggression. Continuous observation and comparing behavior to normal patterns help determine if stress persists, allowing interventions to restore a calm environment.
Do gouramis recover faster in planted tanks?
Yes, plants provide hiding spaces and familiar landmarks. A well-planted tank offers comfort during environmental changes, supporting quicker adjustment and reducing stress-related behaviors.
Can water conditioner improve recovery?
Yes, conditioners that neutralize chlorine and chloramine stabilize water chemistry. Maintaining clean, safe water reduces stress, supports beneficial bacteria, and promotes faster adaptation after cleaning.
Is patience important during adjustment?
Absolutely. Gouramis take time to readjust. Rushing changes or handling them too frequently prolongs stress. Allowing gradual adaptation ensures they regain normal behavior and remain healthy.
Do gouramis show different reactions based on personality?
Yes, individual temperament influences response. Some are bold and explore quickly, while others are shy and cautious. Observing each fish allows personalized care, ensuring comfort and reducing stress.
Can stress from cleaning affect growth?
Chronic stress may slow growth by affecting appetite and metabolism. Maintaining stable conditions and minimizing disturbances ensures proper nutrition and development, especially in younger gouramis.
How important is water testing post-cleaning?
Regular testing ensures stability and prevents stress caused by chemical imbalances. Monitoring ammonia, nitrite, nitrate, and pH helps maintain a safe environment and supports quick recovery.
Are gouramis sensitive to tank crowding after cleaning?
Yes, crowded conditions increase stress, particularly when hiding spots are reduced. Ensuring enough space and adequate shelter helps them feel secure and minimizes aggressive or withdrawn behavior.
Can floating logs or artificial caves help?
Yes, these additions offer extra hiding spaces and landmarks. They provide security while the fish readjust, encouraging normal swimming and feeding behaviors, and reducing stress after environmental changes.
Should I avoid tapping the tank during adjustment?
Yes, vibrations and noise can worsen stress. Minimizing tapping, sudden movements, and loud sounds during cleaning or observation supports calmer behavior and faster recovery.
Does water clarity affect comfort after cleaning?
Yes, cloudy or disturbed water can confuse or stress gouramis. Gentle cleaning and careful substrate handling reduce debris, maintaining clear water that promotes confidence and normal activity.
Can stress cause color fading?
Yes, temporary stress may dull colors. Once the fish readjust and water conditions remain stable, natural coloration typically returns. Maintaining stable conditions and minimizing disturbances supports vibrant, healthy fish.
How important is tank cover during cleaning?
A secure lid prevents sudden jumps or escape attempts. It also reduces light fluctuations, offering a sense of enclosure and safety during maintenance.
Are gouramis affected by water vibrations from pumps or filters after cleaning?
Yes, strong vibrations can increase stress. Positioning pumps carefully and adjusting flow rates minimizes disturbance, helping gouramis feel secure and maintain normal behavior.
Can gentle interaction help calm gouramis?
Yes, calm, minimal handling and feeding by hand can reassure gouramis. Overhandling or sudden movements can worsen stress, so gentle interaction supports recovery and confidence.
Does tank background influence comfort?
Yes, solid or natural backgrounds reduce visual stress. They provide a sense of security and limit sudden external movement that could cause anxiety during adjustment periods.
Is it beneficial to maintain similar water chemistry after every cleaning?
Absolutely. Consistency in pH, temperature, and hardness prevents stress. Gradual adjustments, if needed, allow the fish to adapt without behavioral or health issues.
Can gouramis sense human presence differently after cleaning?
Yes, stress may make them more cautious. Regular, calm interaction helps reinforce trust, while avoiding sudden movements ensures they do not feel threatened or displaced.
Do gouramis react to shadows during cleaning?
Yes, shadows can startle them. Minimizing overhead movement and bright light changes reduces anxiety, allowing the fish to explore and readjust without unnecessary stress.
Is acclimating new water important during cleaning?
Yes, matching temperature and chemistry prevents shock. Slowly introducing new water maintains stability, reducing displacement effects and supporting faster recovery.
Can multiple stressors combine effects?
Yes, water changes, decoration movement, and noise can add up. Managing each carefully ensures gouramis remain comfortable and prevents prolonged stress or behavioral issues.
Are gouramis more active at certain times post-cleaning?
Yes, they may explore more during calm periods or when lighting is consistent. Observing these patterns helps assess adaptation progress and comfort levels.
Does tank size affect hiding behavior?
Larger tanks offer more options, reducing visible stress. Smaller tanks can make hiding spots limited, so placement of decorations is critical to provide security and reduce anxiety.
Can stress influence social hierarchy?
Yes, stressed gouramis may become more aggressive or submissive. Ensuring adequate space and hiding areas minimizes conflict and maintains harmony among tank mates.
Is monitoring food intake essential after cleaning?
Yes, appetite changes indicate stress or discomfort. Keeping track of feeding habits helps identify issues early and allows adjustments in care or environment.
Can using similar decorations help adaptation?
Yes, consistent decorations maintain familiar landmarks. This reduces confusion and helps gouramis feel secure while exploring or establishing territory after cleaning.
Do gouramis interact differently with tank mates post-cleaning?
Yes, some may hide or assert territory more. Observing these interactions ensures all fish remain comfortable and helps prevent unnecessary stress or conflict.
Are gouramis sensitive to vibrations from cleaning tools?
Yes, sudden vibrations from nets or siphons can startle them. Gentle, slow movements minimize stress and prevent erratic swimming or hiding.
Can gradual water changes improve long-term comfort?
Yes, partial, incremental water changes reduce displacement and maintain water quality. This approach minimizes stress and supports consistent health and behavior over time.
Does water flow intensity matter for post-cleaning adjustment?
Yes, strong currents can overwhelm gouramis. Gentle flow encourages exploration without causing fatigue, helping them regain normal behavior safely.
Is it helpful to track behavior patterns over days?
Yes, observing swimming, hiding, and feeding over several days reveals adaptation progress. Early detection of stress allows timely corrections to water, layout, or care routines.
Can temperature-matched water prevent shock?
Yes, introducing water at the same temperature prevents sudden stress. This ensures stability and supports recovery after cleaning or partial water changes.
Do gouramis show signs of curiosity after adjustment?
Yes, once comfortable, they explore decorations, interact with tank mates, and resume feeding. Normal activity indicates they feel secure and adapted to the environment.
Are certain hiding spots preferred?
Yes, gouramis favor places that mimic natural cover. Observing preferences allows placement of plants or caves to maximize comfort and reduce stress after cleaning.
Can repeated exposure to tank cleaning reduce stress?
Yes, gradual, predictable maintenance routines help gouramis adapt faster over time. Consistency builds familiarity, reducing anxiety and displacement with each cleaning session.
Do gouramis respond to consistent feeding times?
Yes, regular feeding provides a sense of routine and security. Predictable schedules reduce stress, encourage normal appetite, and support overall well-being after tank changes.
Can stress cause temporary lethargy?
Yes, brief inactivity is common after environmental changes. Providing calm conditions, hiding spots, and stable water allows gouramis to regain energy and return to normal activity safely.
Does lighting intensity influence comfort during adjustment?
Yes, sudden bright light can startle gouramis. Maintaining consistent light intensity supports a stable environment, reducing stress and promoting normal behavior after cleaning.
Are gouramis affected by chemical cleaners?
Yes, strong cleaners can harm fish and disrupt water chemistry. Only use aquarium-safe products, rinse thoroughly, and avoid residues to maintain a safe environment for post-cleaning adjustment.
How important is minimal handling?
Minimizing handling prevents stress and injury. Gentle maintenance and observing behavior without frequent disturbances allow gouramis to adapt confidently to their cleaned habitat.
Do gouramis prefer gradual environmental changes?
Yes, slow adjustments in decorations, water parameters, and flow help them maintain comfort. Abrupt changes increase stress and may disrupt normal behavior or appetite.
Can stress affect social interaction long-term?
Prolonged stress may alter territorial or social behaviors. Maintaining consistent conditions, hiding spaces, and monitoring interactions helps preserve normal relationships among tank inhabitants.
Is it useful to note individual fish responses?
Yes, each gourami reacts differently. Tracking behavior allows tailored adjustments, ensuring comfort, reduced stress, and a balanced environment for all individuals.
Can floating leaves improve post-cleaning comfort?
Yes, floating leaves provide cover and soft shadows. This offers visual security and reduces stress while gouramis explore or reestablish their territory.
Does partial lighting help stressed fish?
Yes, softer, consistent lighting reduces anxiety. Gradually returning full brightness allows gouramis to adjust without startling them or causing erratic movements.
Can stress affect breathing?
Yes, rapid gill movement or heavy breathing indicates stress. Monitoring water quality and minimizing disturbances
Cleaning a gourami’s tank is an important part of maintaining a healthy environment. Regular maintenance keeps the water clear, removes waste, and ensures that your fish have the proper conditions to thrive. Gouramis are sensitive creatures, so even small changes in water, decorations, or temperature can cause them to feel unsettled. Observing their reactions after cleaning is a key step in understanding how they adjust. Noticing hiding, unusual swimming, or changes in feeding helps identify temporary stress. Over time, most gouramis readjust quickly if the environment is kept stable and consistent. Patience during this period is important, as rushing changes or frequent disturbances can prolong their discomfort. Simple steps, like maintaining familiar landmarks in the tank and providing hiding spots, create a sense of security and allow them to explore at their own pace.
Water quality is one of the most significant factors affecting a gourami’s comfort after cleaning. Sudden changes in temperature, pH, or hardness can increase stress, while maintaining stable conditions ensures they remain healthy. Partial water changes are preferable to full replacements because they preserve beneficial bacteria and prevent shock. Cleaning decorations and substrate gently, rather than removing or scrubbing everything at once, reduces disruption and keeps the fish familiar with their surroundings. Feeding routines should remain consistent, with food placed in areas where gouramis feel safe. Gentle water flow and minimal noise during maintenance further support their adjustment. Over time, these consistent practices not only reduce stress but also encourage normal behavior and regular feeding. When the fish feel secure, they resume exploring, interacting with tank mates, and maintaining their usual activity levels.
Understanding your gourami’s individual behavior is equally important. Each fish responds differently to environmental changes depending on age, temperament, and previous experiences. Some gouramis are bold and adapt quickly, while others may hide or become cautious for longer periods. Monitoring their reactions helps determine whether adjustments are needed to the tank layout, water conditions, or care routines. Providing adequate hiding spots, consistent lighting, and gentle interactions creates a supportive environment that encourages confidence. Recognizing signs of stress early prevents long-term health problems and ensures a balanced, calm habitat. By maintaining stable conditions, observing behavior carefully, and making gradual adjustments, gouramis can remain comfortable and healthy even after regular cleaning or minor changes in their tank.

