Optimum Amount to Feed

[ppp]

I stay in Malaysia where the water temperature is 26-28C practically all year round. Although I'm a relative newbie, I've been on an extremely sharp learning curve for the past 18mths.

Currently I have 20 koi, averaging 65cm, in my 100 tonne pond. I've read that koi should not be fed beyond X% of their body weight, X varying depending on the size of the fish. This has not really helped me as I have never weighed any of my koi and I don't weigh the food (Saki Hikari) either.

With the guidance of my dealer here, I settled on 20 handfuls of food a day. This total amount is then divided by the number of times I am available to feed them for that day, this number typically varying between 5 and 8 times.

My koi have grown exceedingly well with this feeding routine, although my dealer has at times wondered whether I was over-feeding them.

Today Fujio Oomo was in town and I asked him, through my dealer, what the optimum amount of feed was for 20 koi of average length 65cm. After some simple calculations, Fujio's answer was 1.5kg. Since I had no idea how many handfuls of food this translated to, I took out my kitchen scale, put 20 handfuls of my Saki Hikari food into a plastic bag and weighed it. It weighed only 0.5kg!!

Now I'm thoroughly confused. I asked my dealer to double check with Fujio again and Fujio insisted that it was correct, according to how much Japanese breeders feed their koi.

1.5kg translates to 60 handfuls of food. In other words, the optimum level of feed is 3 handfuls per koi per day, assuming 65cm koi. Does this sound right to you guys? It does sound kind of excessive to me and I wouldn't want my koi to get hit with the many kinds of internal problems normally associated with over-feeding.

Please help.

[PapaBear]

I'll be interested to hear what others have to say on this subject. Your circumstance is different from most posters on this board as you have warm temperatures throughout the year, while most of us experience variable seasons which influence feeding rates considerable.
At 65 cm your Koi should weigh in at roughly 10 lb (4.5 kg) each.
You have 20 Koi so your total fish weight is 200 lb (91 kg) total fish weight.
Koi metabolic rates are variable according to water temperature.
At 34 deg F (1 deg C) their metabolism is at baseline Factor of 1 (minimum) for stasis survival. Virtually zero caloric intake is needed to live for extended periods, but they do consume stored fat to breath and circulate blood,.so stored food is consumed.
Every 18 deg F increase in temperature doubles their metabolic rate, so at 52 deg F (11 deg C) their metabolic rate has doubled to 2, and caloric needs likewise double. That is about where we in America begin feeding lightly.
At 70 deg F (21 deg C) their metabolic rate doubles again, and their metabolic rate is at 4.
At 88 deg F (31 deg C) it doubles again for a metabolic rate of 8.
You are averaging 81 deg F (27 deg C) so the metabolic rate would be roughly 6.5.
BTW, I'm putting all of this information on here to help myself think through your situation, not to instruct you. Now I want the real experts to speak up and give the best answer for the health and growth of your fish.

What has been recommended to you by Oomo is 3.3 lb (1.5 kg) per day, which works out to 2.65 oz (75 grams) per Koi, which is about 1.7% of their body weight per day if my calculations are correct. Oomo is likely looking for best growth feeding rates, as that is what breeders are striving for.

[ppp]

Thanks, Larry. So would you feed that kind of amount daily during your summer growing season? Maybe slightly less to adjust for your cooler waters?

Looking forward to input from others too..

[PapaBear]

From all I know Oomo's recommendations are correct for your fish and water temperatures. It takes about 2 hrs at your temperatures for food to pass through the gut, so dividing the feeding into 8 times per day should minimize waste and maximize their ability to digest it well. There are some ponders with auto feeders that have them programed to divide the desired amount of feed into small numbers of pellets every 1/2 hr 1 hr. In this way the Koi are ingesting small quantities continually, which mimics how Carp feed in the wild.

[RayJordan]

Several factors that are very important but difficult to calculate from a set formula.

#1 - It is critical to not feed more than your filter system can process without adversely affecting water quality.. Maintaining low levels of DOC's(surface foam), Nitrates, and near saturation levels of dissolved oxygen are a must for koi to reach their potential.

#2 - It is critical that koi not ruin their body shape and get too fat.

#3 - If grown too fast some koi can lose their color and pattern.

Also koi are individuals and will eat, grow, develop, put on fat, etc. differently. Some with be behind and some will be ahead of the rest no matter what you do.

Of your 20 koi pick out the two or three of the best and focus on feeding your pond to maximize their potential.

[ppp]

I actually do have an autofeeder but I don't use it at all. It takes the fun out of koi keeping! To me the best part of koi keeping is feed time. Auto feeding takes that personal touch away.

My filter is reasonable sized (pond tonnage 100 tonnes includes the 20 tonnes filter) and I have a bakki shower too. Yes, the fish individually develop at different paces. Some outperform whilst others underperform. The issue at hand, I guess, is whether by following Oomo's feed rate, the outperforming fish will do even better and the underperforming fish will no longer underperform.

[Erns]

I had this discussion recently with some serious experts and I can tell you the following.

1. Oomo is obviously correct in what he told you. (he is the ultimate expert!!) Bear in mind he is assuming a top of the line filtration system that can actually handle this much waste. The fish will rearly suffer from high feeding, it's the filtration system and water quality that will go first. Also keep in mind you will need some current to maintain good body shape with heavy feeding, they will need to turn all that protien into muscle just like an athlete on a high protien diets does.

2. This is why is is so challenging to keep jumbo koi. To get 'n +75cm koi in top condition to show you will need to feed a koi like that up to 3% of its bodyweight per day! If you have 20 of this size with the goal of showing them that amounts to some serious filtration and loads of food.

3. To keep the koi and your filtration in good shape you can work on 1- 1.5% and everybody will be happy! I've got a friend with 14 koi ranging from 65 - 80cm and he is feeding up to 1kg per day. His water is good and he wins all the top prizes every year. His pond is also only 30 tons. So you don't have to go extreme. i guess it depends on what your goal is and if it is showing what the standard for your local shows are.

[ppp]

I'll be starting a month long renovation on my pond in 10 days' time, mainly to improve the bakki shower system (installing a more powerful single pump to replace the existing 2 small pumps - this increases the turnover rate per hour, plus to make the bakki shower shower directly into the pond instead of into a retention tray which spills the water into the pond as is currently so). And also to install a series of micro bubble diffusers to replace my existing conventional airstones. I think my filter system is already very good, growth rates are excellent, but I'm just trying to make a good thing even better.

Current in my pond is strong below the water surface and my koi do get lots of decent exercise.

80% of my koi are show quality but my priority is for personal viewing rather than shows. And yes, the standard of shows in Malaysia is very high. Last year's GC was a Sakai Benibana kohaku 89cm. Sakai wanted to repurchase it for USD 120,000 (or thereabouts, I think), but the owner wasn't willing to part with it. The koi is the last in the Benibana line, which is why Sakai wanted it back so badly. It's not mine, by the way.

[ppp]

Here is a photo of last year's Malaysian GC.

[Erns]

Quote: Originally Posted by ppp I'll be starting a month long renovation on my pond in 10 days' time, mainly to improve the bakki shower system (installing a more powerful single pump to replace the existing 2 small pumps - this increases the turnover rate per hour, plus to make the bakki shower shower directly into the pond instead of into a retention tray which spills the water into the pond as is currently so). And also to install a series of micro bubble diffusers to replace my existing conventional airstones. I think my filter system is already very good, growth rates are excellent, but I'm just trying to make a good thing even better. Current in my pond is strong below the water surface and my koi do get lots of decent exercise. 80% of my koi are show quality but my priority is for personal viewing rather than shows. And yes, the standard of shows in Malaysia is very high. Last year's GC was a Sakai Benibana kohaku 89cm. Sakai wanted to repurchase it for USD 120,000 (or thereabouts, I think), but the owner wasn't willing to part with it. The koi is the last in the Benibana line, which is why Sakai wanted it back so badly. It's not mine, by the way.

Why don't you show us your pond. There is a thread going on this. Would be nice to have a 100 ton Malaysian pond on there!