Oxygen is essential for all living beings – including underwater creatures such as fish and aquatic plants. Without it, they cannot survive. Unlike humans, pond life gets its supply of oxygen from the water, and this is our responsibility to maintain. Ponds that are neglected or very rarely cared for will see their aqua life start to perish. Therefore, it’s your duty to keep your pond thriving and healthy.
If the oxygen level within a pond is extremely low, it’s likely fish will not grow properly and may even die. Typically, larger fish will die first as they need much more oxygen than smaller species.
How much oxygen do fish need?
Research has shown that fish need a minimum of 5 parts per million (PPM) of oxygen to live just a few days, but levels of up to 14 would be advised to keep them in good health.
Be aware that if fish have died and risen to the surface of the pond, it’s wise to remove the remains straight away. Once they start to decompose, there is a greater need for oxygen within the water, which may lead to other fish passing away.
Signs to look out for in a non-oxygenated pond:
- Fish rising to the surface (a sign they are desperate for air)
- Fish moving to waterfalls or fountain sections of the pond (Where more oxygen is present).
Another key sign of being aware of is the growth of algae. These plant species consume more oxygen than your fish could ever dream of once it starts to rot, hence the need to eliminate them from your pond. The good news is that there are specialised treatments that can help resolve the issue. When oxygen levels are high, algae growth is unlikely as the good bacteria instead consumes nutrients and prevents odours.
What can you do about it?
The first port of call would be to purchase a specialised aerator pump from water-garden.co.uk, which stimulates the flow of water and discharges harmful gases which would otherwise come into contact with the pond water.
The use of pond aerators should be a standard procedure for all pond users, especially if the pond depth is 15cm or greater. If you have a large pond, it may be the case that you need to use multiple diffusers to pump oxygen around the full size of the pond. If you’re in any doubt, you can also purchase oxygen testing kits to monitor oxygen levels before they dip too low.
Secondly, it would be highly advised to try and keep the pond’s temperature as cool as possible. This is, of course, easier said than done during the summer months, but water at warm temperatures of around 60 degrees Fahrenheit carries much less oxygen. With that said, you should aim to incorporate plants that provide shade, such as water poppies and water lettuces.
As a final note, we hope this blog has given you a helpful insight into how to keep your pond oxygenated throughout the year.