Garden Pond Water Ammonia

There Is A ZERO Tolerance When It Comes To Ammonia Levels In A Pond!

If Your Test Kit Reveals The Presence of Ammonia … You’ve Got Problems

You need to maintain certain parameters in your pond water if you desire to add Koi (or other types of pond fish) to your garden pond. I’ve said this in other articles, but I’ll say it again: you really need to become a “water keeper” rather than a “fish keeper”.

If you learn how to maintain “healthy” water, you will more than likely NOT experience many of the completely unnecessary problems that novice and/or unwilling-to-learn hobbyists so often encounter.

Koi in your garden pond are wonderful and certainly eye-candy, to say the least, but they won’t remain “eye-candy” for long if the health of the pond water is ignored. There is no getting around this issue! Koi are not pond ornaments and they deserve the same care and consideration we give to our other beloved pets!

How Does Ammonia Get Into Our Pond Water?

Ammonia is the primary waste product of Koi and pond fish, and is excreted approximately 75% via their gill tissue, and approximately 25% via their kidneys. Ammonia can also accumulate from the decay of fish detritus, food and other organic debris derived from protein.

Ammonia causes nasty things to happen to your Koi: reddening of their skin and damage to their gills happens because ammonia is so caustic. Your poor fish, suffering from ammonia toxicity, will isolate themselves and lie on the pond bottom. They will clamp their fins and will secrete excess slime.

Probably no surprise, they are now more susceptible to parasites and bacterial infections. Ammonia depresses their immune system at very low levels … even below 0.25ppm.

It Is NOT Acceptable To Have A Detectable Ammonia Level In Your Pond Water!

What Can Cause Ammonia Accumulations?

99% of the time we can point the finger to one or a combination of these problems which cause the ammonia level to rise:

  1. Over stocking the number of fish in relation to gallonage
  2. Over feeding
  3. Inadequate filtration in relation to gallonage
  4. Inadequate turnover rate of the pond water volume
  5. A brand new filter that has not yet “cycled”

Pond water ammonia scale

Without going into very scientific explanations here, please be assured that ammonia is less toxic to fish below a 7.4 pH. However, when the pond water pH is higher than 8.0 most ammonia becomes more toxic.

So, if you are experiencing the problem of ammonia in your pond water, care must be taken to not increase the pH level (for example when performing a partial water change-out.)

Reducing Ammonia Accumulation

Ammonia Is A “Silent” Killer of Scores of Pond Fish & Koi

Your #1 Line Of Defense Will Be Daily Water Change-Outs Of 20% – 40%. Make Sure To Use Dechlorinator With Each Change-Out!

Because the five most common reasons for ammonia spikes are listed above, I’ll offer what to do if handling one, or a combination of, the above culprits. However, in almost all instances daily water change-outs of 20% – 40% will be your best course of action. Make sure the change-out water has a similar temperature and pH to the pond’s.

Here are additional things to do along with the water change-outs:

Brand new filtration system: only TIME will allow the good bacteria (called nitrosomonas) that process ammonia to get established in a filter system — it takes approximately 6 weeks time. So, it is best to not have too many fish at this point, and not to feed them too heavily. Patience is a virtue with new ponds. Let the good bacteria colonize. If you don’t get “Koi crazy” at this point (don’t over stock the pond) and you don’t over feed them because “they just look hungry all the time” (Koi are little piggies…believe me, they won’t starve) you should not have problems getting through the initial 6 week “new cycle” phase.

  • Established filter, but you’ve got ammonia problems: if you’ve got too many Koi … sorry but you’re going to have to thin the herd. If every time you feed (2 times a day is fine, 3 if you wish during warmer weather) there are pellets left floating after approximately 10 minutes … then you’re over-feeding. Cut back on your portions!
  • Inadequate filtration and/or inadequate turnover: this is tough for me to address specifically, because there are so many factors relating to these two issues, however you must have a big enough filtration system to constantly remove fish excrement and other debris from the pond water and you need to “turnover” the total pond water gallonage at least every 1-1/2 to 2 hours.

NOTE: I do NOT know how many gallons your pond contains; I do not know how many fish you’ve stocked and I do not know the efficiency of your filtration system, so PLEASE understand I am generalizing. The turnover rate I’ve mentioned is geared for ponds up to about 5,000 gallons that have excellent filtration and proper stocking levels.

Obviously, you must figure out what is causing the ammonia spike. After you address and correct the situation, continue to monitor the water parameters using your test kits, and hopefully in not too long of a time (except if you are going through the 6-week new filter cycle) you will find that your ammonia test kit readings will be zero.

If you’re dealing with poorly designed or undersized filtration equipment well, you’ve got decisions to make. Either spend more money to upgrade or cut way back on the number of Koi you keep (less fish in more gallons per fish) … I think you get my drift. But I believe you will agree by now that dealing with water quality issues is a DRAG! So, whatever it takes to get your ponding experience into a positive realm should be your goal.

Continue to monitor your pond water. Don’t take things for granted … check the pH and ammonia levels once a week after you get your pond back on track. The few minutes it takes to do these tests is nothing compared to what you may end up going through by becoming lackadaisical. Besides the hassle of dealing with pond problems, you could end up killing all the Koi.

Don’t Be A “Fish Fixer” … Please Become A Dedicated “Water Keeper”

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