Seeing your sick goldfish or koi is distressing because more often than not you do not know the reason for the poor health of your goldfish or koi in your fish pond.
As soon as a pond fish health problem is suspected the first thing to do is to test the pond water and take a good look at how your goldfish or koi are behaving. This will give you a good clue as to what to look for. Ben Helm gives this excellent advice concerning your goldfish or koi fish behaviour …
“Of course, a change is only noticeable if you are confident of identifying ‘normal’ fish behaviour. You can only get a good feel for your fish’s behaviour by watching them regularly and getting accustomed to typical behaviour.
Watching out for how long they usually take to come up to feed, how they usually respond to your shadow and whether certain fish in the pond are always more reluctant to feed than others are all important. It is these idiosyncrasies that make both your pond unique and you the best person to assess fish health – almost at a glance.” He says look out for ..
- Fish Sulking. Sitting on the pond bottom or hanging just under the water’s surface. Fish are sluggish in their escape response when approached at close hand.
- Loss of appetite. Fish do not respond at feeding time. Feeding fish with floating pellets is an ideal way of assessing the health of all of your fish. You should make a mental note of their number at feeding time and to see if any are abnormally reluctant to come to the surface.
- Fish have fins clamped close to the body with dorsal fin not visibly erect. The fins on a healthy fish should be well splayed, tight and erect. Erect fins can be compared to a glossy coat of a cat in that they both indicate state of good health.
Testing pond water as precursor to resolving pond fish health problems …
Many problems with pond fish health or sick goldfish start with pond filter problems This is why you need a pond filter whenever you keep fish … either koi or goldfish. Poor water quality might not be the direct cause of the sick pond fish but just as we get sicker easier whenever we breathe polluted air or smoke cigarettes for example so do koi or goldfish in a polluted water environment … remember a pond filter’s first job is water purification.
If all fish are less inclined to feed or are seen hanging and gasping at the surface then it is quite likely water quality is the problem that seems to be fish health related.
Fixing the water quality problem may not even cure your fish health problem but it can prevent deaths and disease spreading throughout the pond
To see if your pond filter is working properly test for Ammonia, Nitrite, and pH at a minimum, and preferably also test for Total Alkalinity and possibly Hardness.
Ammonia (and also nitrite) is the most lethal to your pond fish health and dead koi or goldfish are likely especially at high pH values. Dead and dying pond fish must be removed from the fish pond because this will also add to any ammonia problem further disturbing the pond fish or fish health balance.
Aquarium Pharmaceuticals basic drop type test kits are most accurate according to experts and you can get them here water test kits and pond treatments.
If you find Ammonia or Nitrite in the pond water
Stop any feeding and start changing pond water … do this every day and replace about 20-40% of the total water volume in the system. But beware of major temperature changes in the system and also remember you may be adding chlorine to the water so spray the water onto the pond surface.
Low dissolved oxygen. If dissolved oxygen is limiting, then fish can become sluggish and even seen gasping at the surface. This is easily remedied for fish health by the addition of extra aeration or increasing the water turnover. So make sure pond aeration is good! Add more air if you can. You can never really add too much air to garden ponds (this is equivalent to putting you in an oxygen tent at hospital). More is always better. Air or oxygen is a critical factor for efficient pond filters and good healthy goldfish or koi ponds
If filtration and aeration are under control and water quality seems fine but fish are still sick, then a disease of some sort must be suspected
Catch koi health problems early
Ben Helm suggests that if only a single or a couple of fish in a pond appear to be affected, then this points to an isolated incident just affecting the fish health of those fish such as localised damage caused by a bash or abrasion as distinct from a pond health problem … but BEWARE. It may be a weak fish succumbing to an isolated ailment such as an internal problem or genetic disorder. A single affected fish may also indicate the start of a larger pond health problem, where so far, only this fish is affected. Single fish must be netted and inspected for any obvious damage or causative symptoms.
If it is clear that the fish is un-healthy or damaged then the fish may have to be isolated and treated separately until good health returns. However, there are cases where there is no external evidence of a cause for a change in behaviour.
Treatment in such an instance may be counterproductive and it may be wise to return the fish to the pond and monitor the fish health progress over the next few days. Check that it’s health does not deteriorate or that other fish begin to show similar symptoms. If, after testing, the water quality is shown to be fine, then the provision of a healthy pond environment and food (if it has an appetite) may be enough to bring the fish back to full health.
Typical pond fish diseases include the following …
- Ulcer disease (caused by aeromonas and pseudomonas bacteria which are almost always result of poor filtration
- Parasite diseases such as gill flukes, anchor worm and ich or white spot. Dr Johnson recommends that you use salt, before you try anything else for parasites. He says “In most cases where fish are still dying off, especially smaller fish and more slowly, Flukes, should be suspected first”.
- There are proprietary fluke control medicaments available … follow instructions carefully If fish losses continue seek expert local assistance
