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How many gallons of water does your pond hold? Are you just guessing?

Here’s how to determine the EXACT number of gallons in your pond.
How many gallons of water does your pond hold?
Are you sure? Or are you just guessing?
Every pond keeper should know the answer to this very important question.

In order to help pond keepers with their koi pond or koi/pond fish problems they must know the amount of gallons in their koi ponds. Guessing can cause death by over dosing or not giving enough pond treatment to cure the koi health problem which also can cause death.

Tired of doing all the calculations and still not knowing for sure
the exact number of gallons in your pond?

Stop Guessing!!
I would like to share a formula with you, using “salt” to determine
the EXACT number of gallons in your pond.*

Here’s how:

Test the salt level of your pond water before you add more salt.
VERY IMPORTANT! You must know the exact weight of the salt you are adding. Then measure the salt level after you added the new salt and use the formula.
One pound of salt added to 100 gallons of water will give you .12%

Here’s the Formula

Volume (gallons) = Pounds of salt added, divided by the change in salt content (in parts per thousand, which is % times 10) X 120 = the number of gallons in your pond.
Don’t stop! Yes, you can do this formula, I’ll show you how easy it is.

If you added 10 pounds of salt and the salinity reading went from .06% to .2% the change in the salinity reading is .14% or 1.4 (.14% x 10 =1.4) 10 divided by 1.4 = 7.1428 X 120 = 857 gallons.

Using the formula:
Pounds of salt added: 10 pounds divided by the change in the salt content, .2% (salt reading AFTER adding new salt) minus .06% (BEFORE adding new salt) = .14% X 10 (change to parts per thousands) = 1.4. (Change in salt content)

10 pounds, the amount of salt added, divided by the change in salt content 1.4 = 7.1428 X 120 = 857 gallons

Note: In order for the gallons of water in your pond to be consistent, the level of your pond water must be the same at the time you used this formula. Make a mark on the side of your pond so you will know the exact level at the time you calculated the gallons.

This formula can be used with a “drop type” salt test kit, however, a salt test kit will give you an approximate salt level. However, our digital “Salinity Meter” will give the exact amount of gallons in your pond to within .01%, now that’s accurate!

Have a fish or pond problem, I’m here to help,

Note from Rick: using this formula could make a big difference in how much medications and water treatments you are now using. Are you using too much medications and over medicating your koi? Or aren’t you using enough medications to really cure your koi?

*I would like to thank “Joe” for sharing this formula with us.

Sick Koi with ulcers and body sores

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h3. Koi Ulcers the Causes and the Cures!

Koi ulcers are open body sores on your sick koi and pond fish. Koi ulcers are a secondary bacterial infection. The primary cause of koi ulcers is “parasites”: Parasites itch you koi casing them to rub against the rocks and sides of your pond. This act is called “flashing”: and it damages the protective “slime coat”: of your koi.

Koi Ulcers can also be caused by poor pond water conditions, rough handling of your koi and pond fish or your koi hitting themselves against sharp rocks or objects in your fish pond. Anything that damages the “slime coat” of your koi fish and pond fish can cause ulcers.

The “slime coat” of a Koi acts like a suit of Armor. The “slime coat” protects your Koi and pond fish from millions of harmful bacteria in your koi pond water like the deadly bacteria “Aeromonas, Pseudomas” from invading your koifish’s body which can cause serious bacterial infections like koi ulcers.

Koi ulcers can appear on your koi fish and pond fish anytime during the year, however, they are found frequently in the spring, when the parasites take advantage of the koifish’s weak immune system, which is at it lowest point at this time of the year.

Plus, you have the problem of poor quality koi pond water because of lack of pond filtering, proper care and pond water changes over the winter months.

Our “Aqua Meds Complete Health Care Kit “: will treat your koi and pond fish for parasites and bacterial infections. For koi ulcers that just won’t heal, our “Ulcer Aid Rx Kit”:/medications/ulcer-aid/ is the product you need to help cure any tough bacterial infections such as koi ulcers, mouth rot, body sores and more.

“*Have Sick Koi or a Pond Water Problem & need Free Help?*”:

Hydrogen Sulfide

Hydrogen Sulfide gas is a gas produced in an-aerobic pockets under water. These may occur anywhere there is deep sand or sediment, or in a sump with thick mulm.

Ponds with more than a few inches of gravel on the bottom will develop noxious gases including methane, Hydrogen sulfide and toxic levels of Carbon Dioxide.

Without Oxygen, some bacteria can respire by using Sulfur, and this creates Hydrogen Sulfide, H2S that is very, very toxic to fish. HACH Chemical has a test for this, (1-800-227-4224) but this should be suspected in any case of fish loss where:

There are no parasites, proven by microscopy,
There are no real Ammonia or Nitrite derangements
The signs are respiratory and
The history has some reference to a stalled filter or the stirring of stagnant gravel or media.
The smell is one of rotting eggs. Losses may be great and they will continue after the H2S is long gone.

Pond Water Testing “Very Important!”

The Importance of Pond Water Testing!

In general, everything you should know about your water is available in some sort of simple test kit. Most kits are very easy to run. You can buy these kits at your local shop or online. Run them at least weekly during the first part of pond opening but monthly or more during the season.

*If fish ever get sick or start acting funny, you should know that SEVENTY PERCENT of fish health problems, INCLUDING vulnerability to disease-causing organisms are related to WATER QUALITY.*

*DO NOT make the mistake of not testing pH and ammonia in particular at the first sign of trouble.*

Koi pond pH

pH is only a measurement of the free Hydrogen ions in the water and is very, very dynamic. The pH can change overnight…In particular, the pH is prone to fall, and “crashes” are quick, and fatal. Interestingly, many people say they checked the pH last week, and are surprised to find that the pH can change overnight.

In simple terms, the pH is supported in range by the carbonate activity of the water (measured in Carbonate Hardness KH) and when the carbonates are exhausted, or overloaded, the pH plummets to 5.5 and kills filter bacteria and fish.

In other situations, the pH can glide downward very slowly over months and thus your resident fish can survive a low pH but the new fish you keep buying perish quickly as they enter the water with a very acid pH.

Check the pH regularly, and also, to get a grip on your ‘safety net’, measure the water’s carbonate activity as Total Alkalinity (TA) as well.

Buy carbonates for the pond in a sensibly priced pH Buffer.

Buy a pH test kit

Buy a Carbonate Hardness (KH) test kit.

pH Crash

pH is only a measurement of the free Hydrogen ions in the water and is very, very dynamic. The pH in your koi pond can change overnight…In particular, the pH is prone to fall, and “crashes” are quick, and fatal. Interestingly, many people say they checked the pH last week, and are surprised to find that the pH in their pond water can change overnight.

In simple terms, the pH in your koi pond is supported in range by the carbonate activity of your pond water (measured in Total Alkalinity “TA” and Carbonate Hardness “KH”) and when the carbonates are exhausted, or overloaded, the pH plummets to 5.5 and kills pond filter bacteria and your koi. In other situations, the pH can glide downward very slowly over months and thus your resident koi can survive a low pH but the new koi you keep buying perish quickly as they enter your pond water with a very acid pH.

Check the pH regularly, and also, to get a grip on your ‘safety net’, measure the water’s carbonate activity as Total Alkalinity (TA) and Carbonate Hardness (KH) as well.

If your KH reading is low, below 125, “Buff-it-Up”: will help.

Dissolved Oxygen

Oxygen is obviously essential to fish health, but how much or how little? Two test kits are available, I would recommend owning one of them. There is another test kit at the pet store or here that is in a little vial you break in the water to be tested and collect a blue sample and compare it to a chart.

Minimum levels would be 5ppm. This level will permit fish to live a few days. Levels as low as 3ppm at least partially explain why fish are dying like flies. Levels as low as 7 could, and should be improved with an air stone o r Venturi pump. Levels over 8 ppm are desirable, but 11 or better (up to 14 ppm) are glorious.

Low Dissolved Oxygen is an underestimated cause of fish losses, particularly because of its synergistic effects with other toxins like Ammonia.

Hypoxia is ‘oxygen starvation’. Most koi ponds are usually well served with venturi retums or waterfalls, but poor pond maintenance, high stocking levels and unusual climatic conditions can lead to low dissolved oxygen (DO) levels.

Low DO is likely to occur in summer. As water becomes warmer it can progressively hold less oxygen: and the fish become more active, leading to a greater demand for oxygen; and the bacteria in the pond and filters need more to, as do submerged green plants including algae.

The role of submerged plants and algae should perhaps be clarified. During photosynthesis, submerged plants release oxygen into the water, which is why they are often called oxygenating plants. However, they also respire at the same time, extracting oxygen from the water and excreting carbon dioxide.

During daytime they produce more oxygen than they consume, but at night, when photosynthesis ceases, respiration continues and they become net oxygen consumers.

Clearly, if the oxygen demand exceeds the oxygen supply then the DO levels will gradually decline and this presents a serious danger to the koi. Common causes of low DO, apart from high fish densities, are heavy feeding and a dirty pond or filter.

A lot of oxygen can be used in oxidising organic waste and, under certain conditions, this extra demand may be ‘the straw that breaks the camel’s back’.

Unfortunately, a DO problem often occurs in the early hours of the morning. when we are not there to see its direct effects on the fish, rather than during the day when submerged plants are releasing oxygen from photosynthesis.

Typical clinical signs of low DO are lethargy and a tendency for the fish to gasp at the water surface and congregate around water returns. Many of these signs are the same as for a gill problem so a test for DO has to be made to be conclusive.

There are cheap DO test-kits available but it is important to follow the instructions carefully to avoid introducing oxygen into the water sample by agitation or by pouring water into the test phial.

If low DO is the problem, i.e. DO is less than 5 to 6 ppm (mg/liter), then additional aeration will help – but it is essential to determine what caused the problem and to take remedial action.

Carbon Dioxide

CO2 can exist in water independently of dissolved oxygen. If the level gets too high, even with normal dissolved oxygen levels, illness will result.

Many atmospheric gases dissolve in water to some extent and carbon dioxide is one of the most important. It dissolves readily to form carbonic acid, giving a weakly acidic solution.

This chemical reaction has important consequences, not only for the eventual chemical content of water, but also for other chemical and biological reactions that occur in the aquatic environment.

The naturally acidic nature of rain allows it to bring other, less reactive, substances into solution. (The pH of naturally formed rainwater is about 5.6 but, as we shall see, local atmospheric and landscape variations can alter it significantly before it gets anywhere near our fish ponds.)

The affinity between carbon dioxide and water has many far-reaching effects on water quality, playing a major role in plant and animal respiration and pH buffering.

Pond Water Changes

Pond Water Change

Water changes are simply the removal of some old pond water, and the replacement of that old pond water with new water. It sounds so simple but there are problems, nationwide.

First, tap water can be chlorinated.

Second, a lot of pond keepers don’t do water changes, at all.

Thirdly, failure to do pond water changes allows the accumulation of background pollution such as phosphates and proteins which inhibit koi fish health and growth.

Finally, water changes need to replenish trace elements and minerals in your pond water which your koi fish need.

Chlorinated and chloraminated water is usually supplied to pond keepers “at the tap” from municipal water supplies. The water company adds these two chemicals to disinfect the water.

Each day, municipal source-water is tested for eggs, spores, ova and cysts of various pathogens. If any are found, it may be that the municipal water authority will double or triple the chlorine or chloramine concentration.

Spritzing the water into the pond slowly will dissipate a lot of chlorine, but will it dissipate all of it? Dechlorinate. By de-chlorinating your tap water, you can be 100% sure the chlorine is gone and will not harm your koi fish.

Many municipal water departments use chloramine for treating your drinking water. Chloramine is a combination of chlorine and ammonia. When your municipal water supply uses Chloramine, you want to use a water conditioner which removes both chlorine and ammonia.

Note: Recently FDA has changed it’s regulations in order to improve municipal water quality.

Many utilities that have used chlorine as their disinfectant in recent years, have changed their disinfectant to chloramines to meet new disinfection byproduct regulations. You never know when your water department will make that change, if they haven’t already?

Many of the water conditioners on the market ONLY remove the chlorine from your tap water leaving the harmful ammonia in your pond water.

When purchasing a water conditioner, make sure the directions state, “removes chlorine and ammonia“. Many water conditioners state “removes chlorine and destroys chloramines”. Sure it destroys chloromines because it removes the chlorine from the chloramines however, it leaves all the deadly ammonia behind.

Some say that the amount of ammonia left behind in your pond water will not harm you koi fish. Why leave any ammonia behind in your pond water? No matter the amount, the ammonia left behind just adds to a bigger work load on you pond filter to remove. Your pond filter has enough work to do just removing the toxic ammonia produced by your koi fish.

Our Aqua Meds DeChlor & More removes both the chlorine and the ammonia from your tap water. Plus, it’s very economical.

In speaking to pond keepers from across the country, I found that about forty percent of the hobby is not doing ANY water changes at all. This accounts for recurring illness among their fish, slow growth, and poor color. This is the most common cause of seven year old Koi that are only seven inches long.

A koi in good pond water with plenty of water changes should grow at least 3-4 inches per year. I encourage you to follow a water change regimen as outlined in the chart below.

“Topping Off” your pond is not a water change. You should know this about water: The solids in pond water do NOT evaporate, nor do many of the chemicals in the water. This means that the nitrates, phosphates, a good bit of the carbon dioxide, all the salt, minerals, etc. never leave the pond and accumulate over time.

As the pond water level goes down by evaporation, you may notice that your fish perk up as you add water back.

There is a transient increase in water quality after the addition of “new” water but it’s rapidly offset by the dissolution of the existing background pollution. So, “topping off” actually concentrates solids and organic chemicals in the water over time. Real water changes are a must.

Ideal Pond Water Change Regimens

Every week 10 percent water change

OR: Every two weeks 20 percent water change

OR: Every three weeks 30 percent water change

Note: Smaller water changes more often are much healthier for your koi fish than larger pond water changes not as often.

No matter which of the above regimens you choose from above, I highly recommend that two to three times per year you should perform a 60-70% pond water change to really refresh your pond water. You will notice a real boost to your koi fish’s health and growth.

Major water change: Simply drain the pond down 60-70% and add dechlorinator. Then refill your pond. Don’t do this in the PEAK of the summer as you might chill your fish. But surely in the early summer and late summer you’ll see how happy your fish are for this major water change.

Note: with a large water change of 50% or more it’s very important to use a dechlorinator which removes chlorine and AMMONIA.

If you are performing the recommended water changes, you should have robust, hungry and healthy fish. Koi fish may still become ill, of course, however, it is much less common if your adding lots of fresh water to your koi pond on a regular schedule. Fact is, if you wouldn’t swim in the pond, your fish shouldn’t be.

Chloramines in Drinking Water


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.

Treatment: Water changes (with Dechlor) 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 water changes are the two mainstays, however.

Water that is warm, high in pH (There’s a test) 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.