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What is a GC Tube (commonly known as UV Light)? Why is it important in a fish pond or water feature pond?

GC Tube is one of the best effective means of disease prevention in a fish pond. It controls the entire koi pond water quality. Such UV rays are widely applied in offices, hospitals and even most residential properties. Ultimately, the main objective we wish to achieve from a GC Tube in a koi pond is to offer/assist the koi a greater chance to combat bacterial disease. Suspended singled-cells or suspended algae will never be an issue with a good effective GC Tube in place.


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Why is there such a wide difference between the retail price for a GC-Tube and a normal UV light from a different manufacturer/brand?

From all our koi pond & water feature servicing experiences, most of the cheaper UV lights available in the market yield weak/poor results that do not last long (there is a good reason why you are paying less/more with the same wattage offered in the market) even though the UV tube is still lit and shining brightly in the fish pond. Poor sterilization patterns resulting in weak sterilization effects on fish pond water after months of usage; wasted electricity consumed but rewarding koi pond owners with lack lustre results an effective UV light should offer; inferior ballast; waterproofing & electrical tripping issues at home..etc are some of the downsides to a normal UV light.


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How does a weak/poor and/or effective GC Tube impact koi pond or water feature pond sterilization?

Below is the spectrum chart of a weak/poor ordinary UVC spectrum against an Effective UVC sterilization (comparison of energy distribution spectrum). In a weak ordinary UVC spectrum, energy consumed produces all class of spectrum rays ranging from Gamma rays (25nm), UV-C rays, visible lights (400nm) and infrared (700nm)..etc. In an effective GC Tube, it can be observed that UV-C wave length is most concentrated in its UVC spectrum with little energy lost to other wave lengths. UV-C is the most desired wave length for use in our ponds (fish pond and water feature koi pond).


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What is a Koi Pond Skimmer? Why is the Water Concepts' "Pro- Skimmer" important to every koi pond?

Skimmer, being a basic, ensures that a koi pond's water surface is rid of fine particles of dirt, road grime, oil film from fish food, and floating fish waste prior to sinking to the bottom of any koi pond gallery (settled waste decomposed will pollute the koi pond water drastically).

A good effective skimmer also prevents large particles such as leaves and petals of flowers from sinking into a koi pond or decaying in koi pond water affecting water quality. A Pro-Skimmer also gives full convenience to our koi pond owners the assurance to remove waste easily. Lastly, a Pro-Skimmer provides the ability to remove warm fish pond surface water (heated up by the sun) and replace with a constant cooler temperature. This action slows down algae growth which most koi pond builders are not aware of at all.

A Pro-Skimmer completes an effective koi pond filter chambers system. Therefore, it is IMPORTANT that the filter chamber MUST be constructed in the correct manner from the start of a koi pond construction to prevent hacking/modification in future when numerous frustrated attempts at water change/maintenance cannot achieve long term clarity.


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What will happen to the kois when we go overseas? There’ll be no one around to feed them.

Just relax and go for your trip as koi can survive up to a month without food.


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My friends advised me to have a deeper & bigger koi pond. Is it really better?

Koi ponds with big water volumes are usually more stable as a hot sunny day and cold night will not affect the temperature of the pond water too much. In a shallow pond (especially one with a big surface area) with full sunlight, temperature changes can be quite drastic between the day and night. Kois always tune themselves to the temperature of the water they live in and sudden changes may lead to stress (and low immunity) which in turn provide an opportunity for bacteria infections to set in. Kois are also able to exercise in a deeper pond propelling up and down whereas in a shallow pond, you would usually see their bodies being more irregular or obese in shape.

Photosynthesis is a process whereby plants (including algae) harness the energy of light combined with Carbon Dioxide to produce food. During the night, the process will reverse and plants (including algae) will then be responsible for taking in Oxygen and releasing Carbon Dioxide. Through air exchanges between pond surfaces (so be careful if you have a wide surface and shallow pond) and the atmospheric air, oxygen will be stripped to the atmosphere. To make things worse, if one were to overcrowd kois in a small pond, both kois and beneficial bacteria living in the bio-filter will be struggling for oxygen in the pond.


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Water in Singapore is safe for human consumption straight from the tap. Is it also safe for my kois?

The water in Singapore contains Chloride and residual Chlorine in the form of Chloramine. Although Chlorine (which is a volatile gas) will dissipate when exposed to air, Chloramine takes a much longer time to break down. Chloramine will kill the nitrifying beneficial bacteria within your filter chambers. Thus, it is very important to keep a bottle of good anti-Chlorine and anti-Chloramine concentrate handy whenever you perform filter maintenance or water change.


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Why is regular basic pond water testing important?

No one can tell (with naked eyes) if your pond water is good or bad in quality unless a water parameter test is conducted. The important water parameters we ought to know in a koi pond are Ammonia, Nitrite, Nitrate, Phosphate, TDS (Total Dissolved Solids) and Dissolved Oxygen.


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What does a Koi Pond filter do?

Koi pond filters, when suitably constructed, should remove ammonia from the pond water. Where does ammonia come from? Break down of uneaten fish food, fish and plant waste (both solid and liquid state) and all other organic waste gives off ammonia. Koi also excrete ammonia from their gills. In Singapore, koi ponds are considered closed-loop and ammonia accumulates fast (very harmful to kois) within the same pond water. Thus, a correct size of filter must be constructed to ensure such is dealt with in proper. Fishes grow fast and never allow the size of the existing koi you are putting in to determine the size of the filter.


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Why is the size of the koi pond filter important?

Many people will choose to have a very small area of filter and a large pond gallery area (where fishes swim) for aesthetic reasons. However, small or insufficient filter will lead to many problems such as water discolouration..etc. Many pond owners neglect the fact that Koi grow fast (as they are always seem hungry), and when the constructed filter is undersized (when your Kois grow twice the size of when you had first bought), water quality issues arise as filter is not able cope with the waste that are produced by the Kois. To make matters worse, as Kois grow bigger, we naturally feed them more . Yet, the more we feed, the more water pollution is caused by themselves and the more harm is done to our Koi, if the waste are not regularly or easily removed. Thus many will ask “For so long, there is no problem in my koi pond but why suddenly?” Initial investment in building a koi pond with correct filter setup is critical.


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Why do we need to grow beneficial bacteria in our pond filter and what good can they do to our Kois?

A mature correct size up pond filter houses beneficial bacteria. These bacteria are responsible for processing the fishes’ waste (ammonia) when pond water passes through the filter media, converting Ammonia (very harmful) to Nitrite (very harmful as well). Also present is another class of beneficial bacteria that is responsible for converting Nitrite to Nitrate (too much of Nitrate is harmful too). Nitrate is the end product of this Nitrification Cycle in your pond water. High Nitrate levels detected warrant immediate water change to prevent harm to your Kois. Algae bloom also directly caused by unbalanced water parameters.


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What is water change and filter maintenance?

Water change is flushing of filter chambers water (including flushing of related pipings) with minimum disturbance to the filter media.

Filter maintenance requires the removal and rinsing of filter media, in the process also flushing out filter chambers’ water as well.

The above requires a correct and proper pond system to ease water change/maintenance job.


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