Feeding koi pond fish in winter

Feeding pond fish and koi in winter is an important aspect to successful pond keeping.

Many pond owners will be aware of the need and benefits of a winter diet, and will ask specifically for such a diet. However, there will be some pond-owning customers who may wish to continue to buy their usual summer diet as autumn approaches. If they select their ‘usual’ try to inform them of their fish’s requirements and how they are likely to benefit from a lower protein, highly digestible diet.

A pond fish’s ability to digest food, (as with all animals) is a function of the efficiency and condition of their digestive system. Not surprisingly, as temperatures drop, a pond fish’s digestive capabilities will also tail off making them unable to completely breakdown and absorb their typical summer high protein diet. This is why there is a need to change to a lower protein vegetable-based diet in autumn and winter

Winter Pond Advice.

All you need to know for your pond and pond fish to survive the harshest winter in a garden pond.

    The feeding habits of many animals will change with the seasons. Farm animals such as sheep and cattle will graze on lush green pasture in spring and summer but be offered concentrates and other man-made feed in the winter. The appetites of pets such as cats and dogs will noticeably increase in autumn through to winter as their energy requirement increases, burning extra food to maintain a stable body temperature. Fish are also renowned for changes in their feeding habits, particularly pond fish, which undergo dramatic dietary changes in autumn and winter. Being cold-blooded, the activity of pond fish is regulated by the temperature of the pond water and their energy requirement will change accordingly. Fish consume more food in the warmer summer waters than any other time in the year and as autumn approaches, their appetite and energy requirements decreases. Consequently, they respond well to a change in their diet that is tailored to such a drop in activity.

    Why Wheatgerm?

    Winter diets are typically based around wheatgerm, which is the high quality protein-packed ‘heart’ of a wheat grain. Such a diet can offer many benefits to your pond keeping customers and their fish.

    1. The low protein content of the diet means that pond fish are offered sufficient energy, but not too much which would be surplus to requirements at these temperatures, leading to the excretion of excess ammonia, which could cause water quality problems.

    2. Highly digestible. At low temperatures, the digestion efficiency of pond fish is reduced. The high quality source of protein in a wheatgerm diet, although reduced compared to a summer food, means that it is more likely to be digested and absorbed efficiently at these lower temperatures.

    Now that the science is out of the way, what does this mean for the customer, their fish and a retailer’s winter pond food needs?

    Why not try placing a notice under your display of winter food?

    3 Reasons to Feed a Winter Wheatgerm Pond Food.

    1. Lower protein diet = Better water quality.

    2. High quality vegetable protein = Digestible at low temperatures.

    3. Vitamin C content = Helps fish to fight disease in autumn and winter.

    When should your customers start feeding wheatgerm diets?

    Most pond fish will feed down to 8oC and wheatgerm food should be recommended as water temperatures fall from about 12oC down to 8oC. The same advice should also be given when winter turns into spring. Customers who have some summer or higher protein growth food left at the end of the summer can still use it to wean fish onto the wheatgerm diet so that their fish can adapt and respond positively to the change in diet.

    Perilous Times

    Autumn and spring can be perilous periods while pond fish hover in a ‘no-man’s-land’ between active and dormant temperatures. During these periods, fish may exhibit unusual behaviour such as huddling together on the pond bottom or lying on their sides; all symptoms of their body winding down for the winter. Unfortunately, a fish’s immune system is also suppressed at these times which makes them more susceptible to disease.

    Feeding a well balanced winter food can aid fish through this barren period and by including additives in the diet such as Vitamin C will ensure that fish are also obtaining health-boosting nutrition, reducing the risk of disease.

    Spring Food

    Wheatgerm diets should be stocked throughout the winter up until spring as a wheatgerm diet should also be the first food to be offered to fish as they venture out of the depths of winter in early spring. This primes their immune system ready for the inevitable bacterial attack. The better they are protected, the better their chances of survival.



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