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Know Your Fish Food and Learn How To Save Money On Feeding Koi and Goldfish

You may want to skip this section if you use only small quantities of food for feeding a few goldfish. I have written this page because it is an area where so much money is spent by koi keepers in particular and it an area that can create many problems particularly when it comes to water quality. I have tried to be objective and in the end the consumer always decides anyway.

Save money on buying koi food

The keeping of koi is a hobby enjoyed by many people worldwide. Everybody strives to get the best from their ponds, filters and of course their fish.

Most enthusiasts incur considerable expense in attempting to get the best out of their koi and one of the most expensive and ongoing cost items is the cost of food. To emphasise this consider that if a fish eats 1% of its weight every day and if there are 50 kg of fish in a pond then the owner will feed 0.5 kg of food every day.

Given these facts it is important to share the secrets to minimising food costs and simultaneously maximising the benefit to the fish and the water quality overall.

The fish quality as measured by rate of growth, absolute size, and colour are determined to a large extent by what and how much the fish eats.

The water quality is a direct function of the food fed to the fish and this fact is rarely discussed and little understood. In simple terms high quality food made from high quality raw materials fed in the correct quantities results in less fish waste products and less waste from the food itself. The lower the waste the better the filter works and the better the water quality and the better/happier the fish must be. It is as basic as that. You can equate this to the difference between high quality dried dog foods and ordinary dried dog food.

Feed your dog the higher quality (also higher priced) food and you will notice far less waste in the garden to clean up and you will also notice your dog needs to be fed a much smaller quantity. The reason is that the dog digests a higher proportion of the food fed and less waste passes through the stomach.

ALWAYS, look at the analysis of the food you buy. The ash, fibre and moisture percentages are worth absolutely nothing. So the higher these percentages the more the money is being wasted.

If a 5 kg bag of food contains 15% ash, 10% moisture and 3% fibre then 28% of the bags contents (amounting to a whopping 1.4 kg) are a total waste of money.

Worse still 18% of the food (ash and fibre pass through the fish) now has to be handled or removed by the koi pond filter - 900 gms of solid waste has to be removed from the pond.

This is why in ponds without bottom drains you see a lot of faeces appearing on the bottom of the pond.

Digestibility of koi fish food

As far as koi food is concerned the type of raw material used governs the digestibility. If you use high-grade raw materials in formulating fish foods then you get high protein and low ash. If low-grade raw materials are used then the ash content will be high.

Think about it! Where does the ash come from?

It comes from low-grade raw materials such as scales and bone that are routine ingredients of normal fishmeal.

The quickest determinant as to whether a food is of potentially high quality is its ash content. High ash content is BAD news for a koi keeper. Herring or whole fishmeal is probably the best raw material used in formulating koi foods because it contains almost everything a fish needs. Whole fishmeal and white fishmeal are not the same.

White fishmeal is the ground-up mixture of whatever parts of the fish that have been left over after processing such as filleting of the complete fish. Such fishmeal is variable because of this reason and it will always contain a high proportion of ash that comes from the scales and bones of the fish. Herring meal or whole fishmeal is what it says - it is derived from crushing the whole fish and not just the low-grade leftovers so the proportion of bone and scale is much lower.

It is common sense that if 100% of a koi food organic content is digestible then most koi will be able to digest up to 100% of the food fed to them leaving nil % to come out the back end and be captured by the filter. Because there is fibre in the organics 100% is not achievable.

In practice the koi keeper is looking for as high a digestibility factor as possible and it should always be verifiable by a detailed review of the raw material composition. The practical implications of high digestibility are important when deciding how much a food really costs.

Fish food understanding continued


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