Growth question

[mingaun]

Hello

I am just wondering if a pond that has mixture of koi's at varying ages from one year to 8 years old has any effect on growth. Will a tosai grow as well in a pond with old fishes or the other question will be will old fishes continue to grow as it should be if one introduces tosais.

I say this is because i notice that small kois tend to feed the fastest and would that leave the big ones that tend to be slow under fed? Would those big ones send 'signal' that ensures they grow the best and suppress the small kois in the same pond.

What do you think?

Mark

[dick benbow]

nother great question.....the japanese breeders tend to keep each year class separate to allow the bigger older slower moving adults to be able to feed properly without being frustrated with faster whipper snappers.

But sometimes with minimum facilities, a person has to do the best they can with what they have....so you could always mix your pellet size so that the smaller and bigger fish have something more their size. The average fast moving tosai shouldn't be able to take a large pellet unless it's one heck of a jumbo

[Lam Nguyen]

My dilemna is the other way around where the smaller koi don't grow as fast as they should because they are intimidated by the larger koi. That's why they just stay on the bottom and don't feed until the bigger koi are full and wonder off from the food source. And hence another dilemna with the koi hobby: how does a backyard hobbyist with one pond collect koi of different sizes? Just something to ponder about.

[dick benbow]

then hit the smaller more timid types with sinking

[MikeM]

Yep. Sinking Hikari wheatgerm is a small pellet suitable for small tosai. Protein level is adequate. Once the little ones reach 10-12", nothing seems to intimadate them. They'll attack floating pellets, create a splash and scare off 30" adults.

[Flounder]

Quote: Originally Posted by dick benbow then hit the smaller more timid types with sinking

I've tried and the big ones fell for it once. After they learn, they'll stay on the bottom & wait for the hikari sinking pellets.


MikeM, do you know any other sinking pellets besides Hikari that's good for the koi?

[MikeM]

I was asking the same question last year about this time. A well-known dealer out of Virginia had a high protein growth pellet made a couple of years ago, but got customer resistance. Most folks prefer floating pellets. So, he had the process changed to a floating pellet. I've asked for the sinking, but not enough requests so far to justify a whole shipment to be run.

AES carries a slow sinking pellet that I found frustrating because nearly a third would float. Also, there is superficial oil that comes off in the water immediately. Still, I got some more this year and found the percentage of floaters was much reduced. A lucky production run? ...I soak the pellets a minute in water to allow the oil to separate and remove the floaters. Then pour off the water and feed the pellets that sank. (Most of the floaters will sink after about 5 minutes of soaking, but the pellets begin to breal apart if soaked that long.) I am not really happy with this feed. It leaves more waste than the other foods I use, but I use it occasionally to give variety.

Since I feed sinking pellets in the morning before taking off to work, and sometimes a little in the evening as 'dessert' after a normal feeding of floating pellets, my koi are getting about 45% Hikari sinking wheatgerm in their diet during the warm seasons. (Nearly 100% during the short cool season we have.) About 5% is the AES 'slow sinking'. The rest is a mix of floating pellets with Hikari Growth as the main ingredient this time of year. My koi much prefer a large floating pellet, and those can be a challenge to find when you do not want much color-enhancing additives. Seems small and medium sized pellets are favored by customers... and my koi think the medium pellets are pretty small. Skimmer gets too many of them before the koi do. When fed a mix of large and medium pellets, my koi go for the large ones and pretty much ignore the little 'medium' ones.

[JasPR]

Mark, the issue you face is not so much about size as it is about physiology. You may have heard of koi as being four season fish. This means that they have evolved as creatures that direct their energy to different growth goals as the water temperature, lighting and dietary mix and quantity, all turn on internal triggers that cause a cascade of hormonal changes and physiological shifts.
So depending on these factors, the things you question, change. Koi Grow in several different ways then. They can get longer, they can get fuller, they can grow sexual organs ( another form of growth).

Koi also grow differently depending on age. As living creatures, koi have stages- juvenile, sub adult, adult and mature adult. And usually, length is just one hint of what stage the koi is in. The reason this is important is because 'before the pellet' ( a 1960's concept) koi ate as wild carp eat. And wild carp have been around for about 40,000 years. So if stop to think about it, carp have been eating ONE way for about 99.999% of their existence and about .001% of their time have eaten pellets.
Even though it is reasonable to think of nishikigoi as a now domesticated race of common carp, they are still basically carp in their general physiology ( not totally, but in this area- pretty much).
The juvenile and young adult carp have a different digestive tract length and digestive rate than a fully mature carp does. They also tend to be mostly carniovorus in this life stage becoming living furnaces for processing protein in the first summer's growth. And growth is everything for survival at this vulnerable stage and size. As you have noticed they also swim differently. This allows for a hunting technique unique to young fish.
Adult and mature koi, on the other hand, root in the mud and begin to take on a more omnivorous diet. There guts are much longer and the digestion phase is longer. The metabolism is slower. These fish benefit greatly from protein, the basic building block of life, but need fats and carbs to utilize the protein efficiently, over time.

I tell you all this to say that if growing koi large is your goal, then koi should be grouped/separated by size and even sex. Then you can focus on the keys to growth for that age group.
If your concern is simply making sure they get enough to eat, I would not worry about that! Use the five minute rule ( all the pellets are gone in five minutes). If you so this twice a day in growing season not know will starve. Koi actually need a lot less food then we tend to feed them. Best of luck, JR

[mingaun]

Quote: Originally Posted by JasPR Mark, the issue you face is not so much about size as it is about physiology. You may have heard of koi as being four season fish. This means that they have evolved as creatures that direct their energy to different growth goals as the water temperature, lighting and dietary mix and quantity, all turn on internal triggers that cause a cascade of hormonal changes and physiological shifts. So depending on these factors, the things you question, change. Koi Grow in several different ways then. They can get longer, they can get fuller, they can grow sexual organs ( another form of growth). Koi also grow differently depending on age. As living creatures, koi have stages- juvenile, sub adult, adult and mature adult. And usually, length is just one hint of what stage the koi is in. The reason this is important is because 'before the pellet' ( a 1960's concept) koi ate as wild carp eat. And wild carp have been around for about 40,000 years. So if stop to think about it, carp have been eating ONE way for about 99.999% of their existence and about .001% of their time have eaten pellets. Even though it is reasonable to think of nishikigoi as a now domesticated race of common carp, they are still basically carp in their general physiology ( not totally, but in this area- pretty much). The juvenile and young adult carp have a different digestive tract length and digestive rate than a fully mature carp does. They also tend to be mostly carniovorus in this life stage becoming living furnaces for processing protein in the first summer's growth. And growth is everything for survival at this vulnerable stage and size. As you have noticed they also swim differently. This allows for a hunting technique unique to young fish. Adult and mature koi, on the other hand, root in the mud and begin to take on a more omnivorous diet. There guts are much longer and the digestion phase is longer. The metabolism is slower. These fish benefit greatly from protein, the basic building block of life, but need fats and carbs to utilize the protein efficiently, over time. I tell you all this to say that if growing koi large is your goal, then koi should be grouped/separated by size and even sex. Then you can focus on the keys to growth for that age group. If your concern is simply making sure they get enough to eat, I would not worry about that! Use the five minute rule ( all the pellets are gone in five minutes). If you so this twice a day in growing season not know will starve. Koi actually need a lot less food then we tend to feed them. Best of luck, JR

Thanks JR,

Thats exactly what i want to know and dread to know as well

Mark

[dechoong]

Quote: Originally Posted by mingaun Hello I am just wondering if a pond that has mixture of koi's at varying ages from one year to 8 years old has any effect on growth. Will a tosai grow as well in a pond with old fishes or the other question will be will old fishes continue to grow as it should be if one introduces tosais. I say this is because i notice that small kois tend to feed the fastest and would that leave the big ones that tend to be slow under fed? Would those big ones send 'signal' that ensures they grow the best and suppress the small kois in the same pond. What do you think? Mark

Hi Mark,

I've not experienced any negative effects of mixing yearlings with adult koi in my pond. I've 12 koi in my pond, the oldest about 6 years of age and the youngest less than a year. 3 of them are over 80cm now and 2 of them about 15cm when introduced into my pond last October. Sure, the small ones will be quite jumpy and avoid the monsters the first couple of days, but they'll mix comfortably within a week.

The 2 15cm tosai (SFF kohaku) is no less than 45cm now in a matter of 7 months, and should easily reach 60cm by October. A 18cm Izumiya Yamabuki bought last December is also about the same size.

However, I would reccomend introducing a pair of yearlings if you plan to mix them with the adults... they'll need less time getting used to the new environment if they have company. The faster they adapt, the more comfortable they are to feeding.

-Dennis