Ozone and its uses in koi keeping.
I decided invest in the installation of Ozone generation systems on my two largest ponds for a number of reasons. Firstly I am investing considerable sums in new koi imports every six months and a large number of increasingly valuable fish are being stocked together. The health risks associated with continual new imports are clearly a risk despite the quarantine regimes in place. So, to me, the expense of Ozone generation systems was more than offset by the potential savings of valuable koi stocks. With my own private koi collection, I have like many of us built up a fairly valuable collection over many years with which one obviously becomes sentimentally attached. This year I have been unfortunate enough to lose several long term members of my collection to bacterial disease which I am convinced was originally brought in Autumn 2000 when I housed a number of new koi in with my own collection through restrictions on water space. I have experienced problems on and off since then culminating in the loss of my all time best Kohaku this spring, although thankfully I now appear to be over the problems. This finally convinced me to take the plunge.
Whilst not a Utopia, since even with the use of Ozone koi can still need individual medication and treatment if required, Ozone systems currently provide the ultimate weapon in the koi keepers armoury in the constant fight against disease and the struggle to maintain superb water quality. We have seen many advancements in koi system filtration – new media, new ‘gizmos’ such as the answer, and organic cure alls such as Genysys and similar products all designed to improve water quality and filtration and thereby ultimately koi health. None however comes close to delivering the benefits of Ozone systems, the benefits of which have long been recognised by the marine camp and like so many other great ideas, only now being accepted in the koi world..
Ozone occurs naturally in the atmosphere. When a molecule of Oxygen, O², is bound to a third oxygen atom, it becomes ozone, or 0³. Ozone is an unstable bluish water-soluble gas with a characteristic smell. In low levels it makes the air smell fresh and its colour makes the sky blue. Ozone is the 2nd strongest known oxidiser known to man and the most powerful readily available water sanitiser. It kills bacteria and viruses 3,125 times faster and is a 50% stronger oxidiser than chlorine. It is unsurpassed for control of many types of common bacteria such as E. Coli and fecal coliforms as well as the de-activation of virus, fungus, mould, mildew and cysts, and is not carcinogenic.
Ozone is nature's way of purifying the air we breathe. As ozone circulates and comes into contact with airborne pathogens, one of the three oxygen atoms detaches itself from the ozone molecule, attaches itself to the cell structure and oxidises it and effectively destroys the cell and thereby kills living organisms. Ozone is nature's way of self-cleaning our environment.
Ozone is such a strong germicide that only a few micrograms per litre are required to demonstrate germicidal action; it destroys all pathogenic and saprophytic microbes in water. Factors like humidity, temperature, pH, ozone concentration levels, type of organism and time, determine the kill rate for pathogens, but its action in water is instantaneous. After oxidation, ozone returns to its original form of oxygen, with out leaving any toxic by-products or residues. Ozone is a natural disinfectant and steriliser and unlike chlorine, it does not produce trihalomethanes ,chloroforms or any other detrimental bi-product in water.
Without dispute, Ozone is the most effective natural bactericide and viricide of all the disinfecting agents.
In our pond environment Ozone: -
For our koi ponds, in order to dose the pond water with the correct amount of Ozone safely we have to install an Ozone generator and a method of introducing the Ozone thus generated into the water in order to achieve the correct level of disinfection. We then have to remove the Ozone from the water before it returns to the pond in order to prevent it coming into contact directly with our koi – which would have lethal consequences.
This is achieved by passing dry air through an electronic ‘gizmo’ that generates Ozone by passing a high voltage electrical discharge through the air passing through the unit. The Ozone thus created is then drawn into a special protein skimmer especially designed for the purpose via a venturi and into a water flow which is pumped from the pond through the protein skimmer. When the Ozone comes into contact with the water it quickly ‘burns’ off polluting organic material and breaks down back into Oxygen. However even though this process takes only milliseconds to seconds the water is bubbled through around three metres of piping before it is returned to the pond to ensure that all the Ozone has done its job and reverted to Oxygen.
As well as disinfecting the water and killing bacteria, viruses and free swimming parasites, the Ozone also kills blanket weed and algal cells. This means that the UV is no longer required and is redundant. Also the water returned to the pond is saturated with oxygen so that the biological filter is able to work at its full potential and strictly speaking, air pumps also therefore become redundant. Ozone is so powerful that it is like having a permanent and very strong dose of Chloramine T or Potassium Permanganate in the pond, without any of the side effects. As the Ozone also burns off proteins, organics and ammonia water clarity is improved enormously and the water sparkles to the point where the colour of the koi is not impeded in any way by the depth of water, and koi that have pure white skin at the surface also have pure white skin 6 feet down.
For us as koi keepers, the other major advantage of Ozone in our pond systems is that it virtually eliminates the risk of cross infection between koi. So even if a fish is introduced into the pond environment which itself is ill, or carrying a bacterial disease, this is much less likely to be transmitted to other koi. Further, any treatment employed to an infected koi has a much improved chance of working effectively as the koi are living in a much cleaner environment, biologically speaking – i.e. in an environment containing very few harmful pathogens.
This is especially noticeable when topically treating surface wounds, which once cleaned, heal much faster.
Similarly if parasites were present on certain koi, the water would still need to be medicated to eradicate the parasites on the body of the koi affected. Any medication used however, will work more effectively as the pond water is maintained at a much higher quality, with a higher Redox potential and with much lest biological Oxygen demand (BOD)
How do we measure the correct dosing of Ozone in the pond water? The ozone dosing is measured in millivolt terms and is expressed as the REDOX level of the water. Normal pond water will have a REDOX level of around 200mv. Sterile water has a REDOX level of around 600mv. The Ozone generator is designed to automatically regulate the ozone dosing to keep the REDOX level at around 380mv, so that the water is not sterile or anything like, since it could not then support life.
For the scientific among us
What is Oxidization?
Oxidization is the process that causes steel and iron to rust, a garden hose to dry up and crack and an apple to shrivel & go brown once cut open and is also responsible for the degeneration or ‘rusting’ of our bodies, causing cellular breakdown. Oxidization or oxidative stress has been linked to many degenerative and chronic diseases including heart disease and cancer. It is also responsible for premature ageing. Oxidization permanently disrupts and damages cell structure
What causes Oxidization?
Oxidization is caused by oxygen molecules that are missing an electron, making them unstable. Oxygen cannot exist in this unstable form and has to be stabilised. The molecules collide with healthy, stable molecules be they in metal, a hose, an apple or living cells and then ‘steal’ an electron in order to stabilize themselves. This damages and de-stabilizes the molecule that they have collided with leaving it now missing an electron itself. The formally healthy molecule is now itself an unstable free radical and will also try to stabilise itself by colliding with another healthy molecule and ‘stealing’ one of its electrons. This creates a knock-on effect that damages and destroys living cellular structure, and in our pond environment this includes parasites, viruses, bacteria, algae or any other living organism.
I have only had the units installed now for about 8 weeks and it is much too early to assess the full impact that the systems are having on the pond environments. Initially on older systems, the Ozone has to burn off much of the pond detritus, algae, blanket weed etc., before it can achieve the desired water quality. It is therefore recommended that pond systems are cleaned out as much as possible in order to achieve ultimate performance in the shortest time
In both my systems where the units have been fitted, the water quality has fluctuated enormously as the units have been ‘cleaning’ the systems for me and only now am I beginning to experience the water clarity promised. In both systems however, there is still much weed growth to clean, and therefore there is still a large amount of suspended material in the water. Unfortunately, in my case it was not practical for me to move all the fish from these ponds to undertake a complete clean out when I installed these units, so I am going to have to be patient whilst the Ozone systems complete the clean up for me.
I’ll report again on progress in the near future.
Malcolm Green