Reprint from 2014/2017 with some updating
I had my second knee replacement surgery, so went looking for a short article for mostly reprint and found this in my files enjoy, I hope.
Well my pond temp is now above 72, so it’s time to start feeding my koi some additional protein in their daily diet. After water quality, I think nutrition is the second most important thing you can do to ensure the health and growth of your koi. You should be feeding your koi at least twice a day now and at 72 degrees you can consider three times a day. At 76/77, I’m feeding 6 times a day. Our webpage has a suggested feeding chart for your review. The quality of your koi food will have a direct effect on solid waste, nitrogen and phosphate levels in your water. The digestibility of your koi food can be observed by the amount of solid waste you see in your pond (best time early AM). Non digested koi food or uneaten koi food left in the pond will lead to increased oxygen demand; additional ammonia-nitrate-phosphate; decreased performance of filters; increase in microbial growth (some bad for koi - aeromonas); and even toxic hydrogen sulfide gas for some poorly designed or poorly maintained ponds. YES, you can overdo protein (been there more than once). The major source of nitrogen (Ammonia-Nitrite-Nitrate) for the average pond is protein found in your koi food. For each gram of ammonia produced by your koi the pond and its filter system will produce about 4.4 grams of nitrate. Carp raised as food fish are fed a diet containing 31 to 38% protein to max their growth with the carp’s metabolic capability to assimilate proteins. Bottom line – If you feed your koi more protein than they can metabolize, it just passes through the koi and becomes part of the fecal material. You pay a higher cost for food and the undigested protein reduces your water quality. Don’t forget you have additional ammonia from any other decomposing organic matter in the pond and don’t forget your source water will also have some nitrogen products (be it low levels). With raised phosphate levels in your pond the koi will do okay at first but algae growth may become an issue leading to conditions that can (depending on fish load) result in fish loss. Koi require phosphate in their diet – but they have a harder time and reduced assimilation rates from fish that have a stomach (i.e. no production of hydrochloric acid).
Got to stop somewhere as this is a complex subject with multiple environmental issues that directly affect this subject matter.
I’ll close with the following thoughts for your consideration:
Don’t keep more than 3 months’ food supplies on hand at any one time.
Keep all food in a cool dry place. (Very important)
Feed your koi a variety of food items (subject for another article).
Observe your koi eating habits. (Best time to observe mouth problems).
Broadcast food over large area (so the little guys can get some food).
For me, if all food is gone in 8 minutes I’m happy.
Remove any food left on the surface after 10 minutes.
Keep the food out of any skimmer during feeding.
What about using an automatic or on demand feeder??
For the science nerd the feeding interval is:
Interval = 40 times the square of W divided by T
Interval = time between feedings in hours
W = body mass, grams
T = temperature, C
(RAS 2nd edition; Timmons; pg506)
r/koi jack
