Why are my fish constantly at the surface?
Fish enjoy routine and will learn your feeding schedule, coming to the surface when they see you. They sometimes stick their mouths out of the water in anticipation. If you give them treats occasionally or feed at different times, they may start to come to the surface whenever you walk out to the pond. Waiting at the surface for food is different than gulping for air. If your fish spend too much time at the surface, it could be a sign of a problem.
Surfacing: Just Saying Hi, or Something More?
If your fish are surfacing frequently, you can run a few tests to see whether they're looking for food or if it's something more.
The first thing you can do is to observe them in secret. Are they still surfacing? You can also walk to the pond at a different time than usual to monitor them before they see you. If they're hanging around at the surface, some with their mouths gulping air, there may be a problem with your pond.
What Does Surfacing Mean?
If your fish are hanging around the water's surface and gulping for air, it could mean there is not enough dissolved oxygen in the water or the pond has a water quality issue. These problems can cause stress. Fish do not handle stress well, which can affect their immune system, making them more vulnerable to parasites and other illnesses.
The Underlying Causes of Surfacing
We know a lack of dissolved oxygen can be the cause of surfacing, but what causes the drop? The warmer the water is, the less dissolved oxygen it naturally holds. This is especially true if water is too still or stagnant. Shallow ponds get warmer faster, but require less agitation to add oxygen. Deeper and larger ponds need constant and more powerful forms of circulation.
Your fish are also more active in the summer, meaning they need more oxygen than in the winter when their metabolisms slow.
Pump Issues
A lack of aeration is the most common reason oxygen levels drop. Your fountains, waterfalls, and aerators should run 24/7 in the summer and warmer springtime. A pond without aeration can quickly become devoid of oxygen in the warm summer months.
Ponds with a waterfall, fountain, or aerator can still have issues if the pumps are not working at full strength or aren't strong enough for the pond. If there is an issue with the pump during the hottest parts of summer, oxygen levels can drop very quickly. Learn how to troubleshoot pump problems and pick the right size pump for your pond.
Increase Oxygenation (Aeration)
If your fish are gulping at the surface of the pond, you can start by increasing aeration. Check your pumps and filters to make sure everything is running properly and nothing is clogged.
You can add a nozzle kit to your pond, or an additional water feature, such as a spitter, to add oxygen to your pond. For an all-in-one solution, adding a Filter Kit with Pump circulates, oxygenates, and filters the water. Going bigger, like adding a waterfall, will add even more oxygen.
Poor Water Quality and Dissolved Oxygen
A water quality issue can cause stress to your fish and affect oxygen levels. If your filter is not working properly or there is too much debris, it will start to break down in the water. Debris can be from runoff, overfeeding, and other organic materials that find their way into the pond. This nutrient increase can promote algae, which also consume oxygen and contribute to poor water quality.
As bacteria break down the debris, ammonia, nitrites, and other harmful gases are released into the water. Overcrowded ponds can produce more fish waste than the bacteria can break down. Adding a Pond Filter can help clean the water and promote beneficial bacteria.
Learn what to do if your pond fish grow too large for your pond and start overcrowding.
Improve Water Quality
If your water quality is poor or you're struggling with algae, you may want to use water treatments to help restore balance. Water treatments are effective, but it's also important to figure out the cause of the water quality issue so you can prevent it in the future.
If your fish seem to be saying "hi" more than usual and spend time at the surface when you're not around, it could be a warning sign of an issue. When the oxygen levels drop in the pond due to lack of aeration or poor water quality, the fish become stressed and go to the pond's surface for oxygen. You can check your filters, pumps, and aerators and perform a water quality test to see what is causing the oxygenation issue. It's nice to be greeted by your fish, but they should only be surfacing to say hi and look for food.
