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New pond syndrome

To those new to the pond world, these three little words can represent a real problem. New Pond Syndrome (NPS) can occur in the first few months of a pond due to a heavy fish stock and raised ammonia and nitrate levels thanks to poor filtration and increased waste. This can kill fish and really dishearten the fish keeper, causing stress and financial loss.

New Pond Syndrome can be caused by adding too many fish, too soon to the pond. This creates a build-up of ammonia which can stress and ultimately poison fish. When fish are stressed they are more susceptible to infections, both bacterial and parasitic. So keep an eye out for fish scratching, spots, and other signs of illness which can indicate poor water quality.

Signs of ammonia poisoning:

  • Fish gasping at the surface
  • Red or purple tinge to the gills
  • Lack of appetite
  • Lethargy, maybe even lying at the bottom of the tank
  • This can be lethal.
There are several things you can do to avoid NPS. Much the same as an aquarium, the solution is to prepare the water and maintain a very low ammonia, nitrites and nitrates level. Keeping these levels low will also reduce the risk of algae growth.

Swell UK have a variety of products that will help fight the problem and maintain a healthy pond:

  • When you fill the pond add some de-chlorinator. This will remove chlorine, chloramine and other pollutants from tap water. Any time you perform a water change a simple dose of de-chlorinator will neutralise the water and make it safe.
  • Use a good quality filter than can cope with the amount of water in your pond. The rule usually used is that double the volume of your pond to makes sure you have adequate filtration for a fish pond. So for example, if you have a 3,000 litre pond, opt for a 6,000 litre filter. That way it can cope with waste and debris, and hopefully cut down on maintenance. However, if you have a Koi pond the original volume must be multiplied by 4, as they produce a lot of waste.
  • Use a filter starter in the pond filter. This will give the filtration system a boost of nitrite and ammonia busting bacteria and mature the filtration system. This will start the process more quickly than the natural way.
  • Using a carbon and/or zeolite filter media will also help purify the water and remove any contaminants. Carbon is also well used to remove traces of taints, odours and treatment residues so you can cover many aspects of pond care.
  • Add a few fish at first. Then using a reliable test kit, test for ammonia and nitrites every few days to monitor the correct levels. You will notice a spike in levels at first, this is normal. Then after around three weeks, if the ammonia/nitrite levels have reduced to zero, you can add a few more fish.
Good pond maintenance is also vital to support fish and plant health. Remove all uneaten food after five minutes, as this will decompose and turn into waste. Also, remove dead plants and sludge from the bottom of the tank, as this is rotting waste and debris that will release toxins into the water.

With a little time, hard work and perseverance, you can hopefully avoid New Pond Syndrome and enjoy a happy, healthy pond.