Water Gardening: Caring for Your Pond Fish

Fish ponds are becoming ever more popular in the United States and around the world Still, even though a lot of folks have joined the hobby lately, there are thousands who have been ponding for tens of years.

Over time, almost all hobbyists develop ‘favorites’ in their groups of fish. Then, instead of viewing fish as simple livestock or decorative items, they take on a personal level of responsibility and keeping them healthy reaches a higher priority. For those of you who feel this way about your fish, here is what I recommend in caring for your fish.

Water Gardening Caring for Your Pond Fish 300x198 Water Gardening: Caring for Your Pond Fish

Water Gardening: Caring for Your Pond Fish


Feeding pond fish has only a very few caveats and precautions which I would like to itemize here. First, even though pond fish are often identified as omnivores, there is convincing evidence that their digestive systems assimilate animal protein [fish meal] much better than plant protein [corn, wheat & soy]. Therefore, I recommend that in the feeding of our pond fish we attend to feeding a diet based on two animal source proteins and one plant source of carbohydrate energy in the top three ingredients, but none of these ingredients should be corn.

Secondly, I recommend that the fish be fed twice daily in amounts that they can consume in five or ten minutes. To do this, simply cast out some food, and when it is gone, reapply another small amount and repeat this until five or ten minutes have elapsed. Repeat twice daily for best results. Feeding five to seven times daily can result in fat fish with ‘arrow’ heads.

Finally, your food should be made with stabilized vitamin C – the best formulation is 1-ascorbyl-2-phosphate.

Special tip on feeding Vitamin C

Dr Lovell at Auburn University proved that supplementing a lot of Vitamin C to our fish will actually IMPROVE their immune response. The value of this should not be overlooked. To supplement vitamin C to our fish, instead of wasting your money on a water additive, simply cut an orange or grapefruit in quarters, and float on the water surface. Within minutes, the fish will be loading up with Florida fresh vitamin C in its best and most assimlatable form.

Basics of Water Quality

There are many important parameters in water quality for you to be aware of, but for starters, and for the long term, here are the two you’ll worry about most.


Ammonia is the primary waste product of fish, excreted primarily through the gill tissue, but to a lesser extent via the kidney. Ammonia can also accumulate from the decay of fish tissues, food and other organic debris derived from protein. Ammonia accumulations cause reddening of the skin and disability of the gills by its direct caustic effect on these surfaces. Fish suffering in water with high ammonia accumulations will isolate themselves, lie on the bottom, clamp their fins, secrete excess slime, and are much more susceptible to parasitic and bacterial infection.

Ammonia is a big problem in new systems because the bacteria that would naturally dissolve ammonia are not established, see discussion of cycle. As well, even in established systems, ammonia may accumulate in springtime when the water is cold but fish are eating, because filter bacteria have not emerged usefully from hibernation.

Ammonia is capable of ionization below pH 7.4 and so in its ionized state is less toxic to fish.

Above pH 8.0 most ammonia is ionized, and so becomes more toxic. Care should be taken not to increase the pH of a system if ammonia is present but the need to drop the pH or restrict oxygenation to tanks of fish to keep pH down is an overrated aberration in the literature.


Water changes and management of the pH near neutral will go a long way to cutting losses from Ammonias, ancillary, less useful modes of Ammonia management include the use of the various water conditioners that bind ammonia, and the application of rechargeable Zeolites to the system filter. I am still going to tell you that time and waterchanges are the two mainstays, however.

Water that is warm, high in pH or deprived of oxygen will have an enhanced toxicity when ammonias are accumulating. These are all important considerations as we try to interpret the varying symptomatology of fish at the same ammonia level, for example, but are affected very differently.


pH is a measurement of the free hydrogen ions in the system. pH is measured on a scale of 1 to 14, but the pH required for life lies between 5.5 and 8.5. Individual species will have varying demands as far as pH. Ignorance of the requirements of each species will result in the death of the animal in question. pH impacts fish in several ways. First, if the pH is too low, a condition called Acidosis results. Symptoms are anorexia, and then production of excess slime, isolation, and resting on the bottom, finally, streaking of the fins, and death will occur.

If the pH is too high, the fish will produce excess slime, and will gasp at the surface. Losses can be major. Alkalosis is hard to reverse once it occurs.

On the other hand, Acidosis is rapidly corrected once the pH is brought up to a suitable range.

pH contributes to the toxicity of Ammonia. At higher pH values, ammonia is more toxic. Below pH 7.2 most Ammonia is ionized to Ammonium and is far less toxic. This has relevance if you are considering raising the pH in a system with accumulating ammonias.

There is a routine, inexpensive test that measures pH, and compares the result to a color chart for the diagnosis.

pH is prone to fall in un-buffered systems and can fall precipitously due to oxygen consumption, accumulation of carbon dioxide, decay of fish and other wastes, and the normal activity of vitrifying bacteria which reduce ammonia to nitrite.

Crashes from a normal pH all the way down to pH 5.5 can occur overnight. At 5.5 the filter bacteria that may have contributed to the crash will shut down, preventing the crash from dropping yet further. In systems where the pH has been chemically stabilized by baking soda, oyster shell or any of the commercial buffers, the pH crash phenomena is not commonly seen.

pH is supported by the carbonate activity in the system. This is measured as the Total Alkalinity.

Water Changes

Water changes are perhaps the best, beginner’s way to good water quality, and success with Koi and other pond fish. I could recommend that you routinely change 20% of the water in that system every week or two. Water changes replace lost minerals in the water, and they dilute accumulated toxins and putative growth inhibitor pheromones.

If you’ve made the mistake of putting gravel in your pond, it would be even better if you siphoned or hydrocleaned the gravel when you did the water change. This removes debris trom the gravel that contributes to deteriorating water quality.

Please consider making routine water changes a part of your fish care protocol.


Medications in fish are over used. Most of your fishes’ health problems are related to water quality. Many medications can have a bad effect on water quality. The reason is this, purification of water is dependent upon the activity of bacteria that reduce ammonias and nitrites into harmless nitrates. When you add these antibiotics to the main system you kill a lot or all of the bacteria that purify the water. Obviously, your intentions are good but this massive die off of filter bacteria creates a problem more severe than a routine bacterial infection of the fish, namely, high ammonias and nitrites will result from the use of these drugs in the main system. Now you have to do major water changes to correct the ammonia problems, and the fish suffer for it. Futuristically, you should use drugs like these in a bath. OUTSIDE THE MAIN SYSTEM.

I recommend that you use salt, before you try anything else for parasites.


Remove submerged plants. Perform a fifty percent water change, and clean the pond as well as reasonably possible without causing undue delay in treatment. Apply one teaspoon of non iodized table salt per gallon of water every 12 hours for three treatments (3 tsp. per gallon). Alternatively, for larger systems, dose one pound per hundred gallons of water every 12 hours for three treatments (3 pounds per hundred gallons). Add all at once in the case of epidemic mortality.

Signs of Disease -

Disease symptoms of note include the following:

  1. Isolation of one or more specimens
  2. Loudness or flashing on the slain
  3. Failure of the appetite.
  4. Milky velvet on the skin
  5. Erosion or rot in the skin or fins.

Do not buy fish with any of these qualities. If you see these symptoms, you are advised to check your important water quality parameters and then correct any abnormality found. If water quality checks out okay, then you would do well to follow the instructions on salting and peruse the free information available on-line at http://www.koivet.com

Quarantine -

Quarantine is the best method to reduce disease introductions. Let me outline a quarantine facility and protocol as if the fish we were discussing were quite valuable.

First, a large facility is required, 100-150 gallons in a round arrangement is good. Dark colored tanks are okay, but if they require the fish to keep stopping and turning results will be less favorable than a round tank which permits endless circular swimming.

It should have a fully cycled filter sponge or other type of effective nitrification system, fully operational. A quarantine with bad water is infinitely worse than no quarantine at all.

Temperature should be 78 degrees in quarantine.

pH should be supported with SeaChem neutral buffer dosed according to label instructions.

You should dose the quarantine with 0.3% salt (Noniodized salt at 3 teaspoons per gallon).

The quarantine should be completely covered because they like to jump out, and that can be costly.

You should check Ammonia and pH in quarantine each day. Ammonia should be ZERO.

You should feed an antibiotic food during the stay in quarantine.

The facility can be safely treated with Dimilin while in quarantine, even with the salt, etc. This will stop the introduction of Lerneiid and Branchiurian parasites. F inally, the quarantine should be of a 14-21 day duration, so long as water quality can be supported with changes etc. as needed.

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