Page 70 - Koi Net - On-Line Koi Magazine - Issue 92

THE SCHOOL OF KOI:

EVERYTHING ABOUT

NITROGEN PART 6

Koen Gevers of ‘The School of Koi’ YouTube
channel shares various aspects of keeping
Koi he has built up over the years.

Koen Gevers continues his series of articles for both
new and experienced Koi keepers. Which he hopes will
provide useful knowledge for Koi keepers worldwide.
In our previous and following articles, an in depth
detailed story, (nearly) everything there is to know about
Nitrogen and its relation to keeping Koi will be explained.

Everything about N(itrogen) – Part 4
In the first 3 Parts about nitrogen I discussed some
articles to explain what Ammonia (TAN = NH Ammonia
³
+
plus NH 4 Ammonium) is, what happens in the Koi, and
how it is excreted. Let’s recap some conclusions. The
nitrogen excretion depends on the time of the food
given, and is by far the most dependant on the amount
of food that the carp eat. If you give them more food,
they also excrete more Ammonia. Larger carp eat more,
but in relation to smaller fish less as a percentage of
body weight. After all, they need less energy in
proportion, so also excrete less Ammonia per kilo of
body weight because they eat less. Koi grow faster if
you feed them the same amount of food divided over
smaller portions, during a longer period per day (multiple
feeding times), which also helps them to cope better
with higher Ammonia concentrations. The excretion of
Ammonia (TAN) reaches the highest values within a few
hours of feeding, and then returns to a much lower
value. So Koi do not excrete a constant amount of
Ammonia all day, which is why it is not calculated easily

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