Understanding “Healthy” Pond Water

Unpolluted Water Is Mandatory for Healthy Koi and Pond Fish!

Become A Knowledgeable “Water Keeper” Not A “Fish Fixer”

Many a wise Koi hobbyist knows that understanding and mastering pond water chemistry is probably one of the most crucial and important aspects of maintaining strong, disease-free fish. I include myself in this group.

I cannot tell you how important it is, at the very least, to grasp and practice the basics of keeping your garden pond water “healthy”. If you get the basics under your belt, I can assure you many Koi and pond fish related problems (ulcers and dropsy, to name two) will become almost, if not completely, non-existent.

Think about this … I’ll offer a rather simplistic analogy to a Koi swimming around in crummy, toxic pond water, but I do believe you’ll get the idea I am trying to convey.

Alright … if you or I continually consume lousy drinking water and breathe polluted air, we are ultimately going to start feeling sick. Soon we’ll be run-down because our bodies can’t fight off all the toxins and other nasties we have been taking in.

Because we’re run-down, we’re vulnerable to illnesses, viruses and the like. Pretty soon we’re so sick there will be no option of us shaking off the problems now afflicting us. To make matters worse, we’re still stuck with terrible water to drink and horrible air to breathe. There is no way that we can recover. It won’t be long before we probably die!

Whoa! This is a sad story but one that happens day in and day out in the world of Koi keeping and backyard garden ponding. Honest. I am not exaggerating.

My experience has proven to me that most people wrongly assume that Koi or goldfish are quite indestructible. That all you have to do is give them some water and maybe a few plants and they’ll survive just fine. Nothing could be farther from the truth.

So … the easy solution to being a successful Koi keeper is to be a knowledgeable and successful water keeper! A healthy aquatic environment for your fish will result in healthy Koi! Really and truly. I am a dedicated “water keeper”. My happy 7 year old Koi are living proof of this philosophy.

pH, Ammonia and Nitrites …

Want Pond Fish? Then Learn How To Maintain Proper Water Parameters

Overcrowding and Lack of Filtration Contribute To Bad Pond Water Chemistry

While this article is written to discuss the merits of understanding water chemistry in relation to having a “healthy” pond, overcrowding and lack of proper filtration certainly go hand-in-hand with the chemistry aspect. I will explore these two issues in other articles, but understand that Koi do “pollute” the water (they excrete the food they eat) and you must continually remove this pollution in order to keep them healthy. You and I could not live healthily and robustly in a cesspool, and neither can they.

Thusly, if you crowd them in a too little pond, and you don’t provide adequate, on-going, 24-hour a day filtration of the pond’s water, then the water chemistry begins to change and bingo! Problems arise.

pH … Koi Appreciate a 7.0 – 8.5 Range

Simply put, pH is the level of acid or alkalinity of the pond water. Think of the extremes of battery acid versus caustic lye. You wouldn’t want to stick your bare hand into either, would you? No way! Well, in the same way, we don’t want to subject our Koi to either of these extremes in their wet environment.

So, it is essential to monitor the pH level in our garden ponds IF we really want to become responsible Koi keepers! Very affordable pH test kits can be purchased at pet or aquarium stores, or on the internet. The tester kit I use and prefer has a liquid that you put one drop of into a little vial of collected pond water. The tester liquid changes the color of the water and by comparing it to the kit’s color chart you can quickly tell the pH of the pond water.

A pH reading of 7.0 – 8.5 is really ideal for Koi, however they can survive in ranges between 6.0 – 9.0. Readings that fall above or below these for too long a period can cause irreversible health problems.

I am not going to address the various issues that can cause pH problems in this article. Please refer to my informative article pH: Strive For Stability for a more in-depth discussion.

Ammonia … A Quick & Silent Killer

I call Ammonia a “silent killer” because you won’t see it in your garden pond’s water nor will you smell it. It is a “quick killer” because if it reaches even minimal levels it damages the Koi’s gills, thusly the transfer of oxygen is blocked and they can end up dying. I guess in human terms we’d say they suffocated.

Ammonia should NOT be detected in pond water! Now, I am once again moving into information that will be covered in the article Ammonia: Toxicity Issues & How To Remedy High Levels. However I have to say that ONLY WITH PROPER FILTRATION equipment will you maintain ZERO ammonia levels.

Where does ammonia come from? Primarily from the Koi! Ammonia is a gas released from the fish gills as a metabolic waste from protein breakdown. There is also a secondary source which includes the bacterial action taking place on solid wastes and urea.

Also, if the pond’s pH increases and the temperature of the water drops, ammonia that is present in the water becomes more toxic. It becomes a vicious circle. So again … strive for a ZERO level at all times.

An ammonia test kit should be in your arsenal. I prefer the liquid drop-type test kit.

Nitrite … Zero Is The Number

Nitrite should NOT be detected in your pond water. With a properly functioning bio-filter you will have “zero” readings. New filtration systems most likely will cause nitrite levels to rise, until the bacterial colonies get established. For more detailed information on healthy filtration systems, please refer to Nitrite: Toxicity Issues & How To Remedy High Levels

Nitrite is also considered an “invisible” killer”. Much like ammonia toxicity, you won’t know it is there UNLESS you are utilizing your trusty test kit! Even a low level reading of 0.25ppm can kill smaller fish. A common indication of a Koi (or other pond fish) that has suffered a severe nitrite spike can be seen in their gill covers. They may be slightly rolled outward at the edges.and do not close flat against the Koi’s body.

This article is a brief overview of the three “top” garden pond water chemistry concerns. In no way do I attempt to imply that this is all a Koi hobbyist needs to know on this subject. I am merely trying to make a strong point in favor of all Koi owners learning to become keepers of healthy, garden pond water for their aquatic pets!

Koi Are NOT Ornaments For A Water Garden … They Deserve Care And Consideration Just Like Our Other Beloved Pets!

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