Hello All

I am needing some advice on improving the growth rate in my main pond. My current specs are as follows:

25000 litres 6mx3.5mx1.2m deep
I have two x .75kw pool pumps one pump runs through a veggie filter, and the other runs through approx 20m of 110mm pipe with filled with bio-balls.

I have four filter chambers that both pumps pull water from. each chamber is 70cm by 70cm by 1.2m deep and collectively they are filled with 12000 plastic hair-curlers and bio-balls with significant air pumping through it

I have a central bottom drain that has an air diffuser on top which has an airpump linked to it doing about 350 litres a min - it pushes bubbles almost 15-20cm above the surface of the pond. I have a second pump 160l per hour that pushes air down a pipe on the side of the pond. with 6 holes releasing a stroing curtain of bubbles.

I reckon that at best I am getting about 2cm a month on some fish and about 1.5cm on others. At the moment I have

1x 60 cm
4x 55cm
20x 25-35cm


I am feed ing Aqua Master Hi Growth mixed with saki-hikario growth.
What am I missing? Is my stocking density too high? Will a bakki shower help?I know I have tons of bio media. I have fairly good qaulity fish and bloodlines are not the issue.
Can some of the experts offer some sound advice please



Thanks

Quinton there are a few simple things required for growth, this is what i have found. As you know i dont own the biggest kois in the club so maybe you must ask the guys with the bigger kois in the club but i am very happy with my growth rates that i get.

On my small tosai koi i get an average of about 3cm per fish, but every now and again you get a koi that grows like there is no tomorrow while the others stand still. I am not sure about my bigger koi as i am not tracking them. I have 2 kois of 60cm + and about 4 in the 50cm range. Then i have 4 kois that are all in the high 35-40cm+ range, all of them where 15cm kois in december.

1. Pond Volume and stocking levels.
This is the most important factor. Your fish will have to share all the resources in the pond. So the less fish you have in the pond or the bigger the pond volume the less the fish will have to share. We are normally told that we should have a 1000L of water for every koi but in truth this is the bear minimum. The more serious koi keepers that keep koi in cement ponds push these levels higher to achieve better growth results. Some of the most common lower stocking levels are 1 koi for every 2500L or at the extreme 1 koi for every 4500L. In japan tthe Japanese breeders push levels even higher to give the koi the best chance the reach its best potential. All the other points that follow are secondary to the stocking level rule.

2. Hi Protein Food.
In my opinion Aqua Master is fine. I feed my tosai Aqua Master Growth and my Bigger kois Shogun. The small pellete shogun sinks mostly while aqua master does not, thats why i still use Aqua Master for my tosai. Hikari obviously kicks ass if you can afford. I just have to look at the growth that bobby gets.

3. Amount of food fed a day.
You control this. A koi feeder is key here. According to the guys on Koi bito feeding a fixed amount over many feedings are beter than feeding it over just 2 feedings. The idea behind it is that once the gut of a koi is full everything it easts after that will cause the food in the gut to be pushed out without being properly digested. So feed a fixed / calculated amount over a long period and then then the little bit of food in the gut will get digested while its waiting for the next feeding. There was also a article that kois absorb more of their food at night...not sure how that works but thats what the article said.

4. Lots of Oxygen
High turnover rates = more oxygen in the water but high turn over rates can also cool the water... Air pumps are thus very important. In my pond i have air in my filtration, air from my bottom drain diffuser, 2 venturis and a waterfall.

5. Heat - water tempreture
As Bobby has found, thicker walls increase the tempreture of your pond water. The way that the water is returned to the pond will also affect the water temp...A bakki shower is great for more oxygen but bad for water tempreture if its out in the open.

6. Light - amount of light during the day.
Its like fooling chickens...the more light the more the kois wil be active and the more they will eat and grow. In the Dec, January and Feb i was feeding upto 12am at night with the use to lights around my pond.

7. Water quality.
Im just refering to Ammonia, nitrate or nitrite. I am not puttig water clarity under this...a mud pond is dirty and yet kois grow like mad.

8 Water hardness
Hard water will decrease growth. Soft water increases growth. There are a few articles regarding this. Total Alkalinity is the key here.

If you are interested, i wrote an article for KOISA regarding this topic.
http://www.koiadventures.co.za/Home.aspx?Page=UsrGeneric.ascx&Rec=296

Hi Quinton
I you do not mind me saying that in my opinion the 110 pipe filled with bio balls is extremely old school and will have a negative effect on water quality. Cutting one open would be something else to experience. I do not say or feel that you are getting bad growth but a 4 tier Bakki shower against your back wall as an additional line will most definitely improve water quality, bring nitrate down and add more oxygen. I believe one can never have enough oxygen. A veggie filter needs to be pretty big to have a serious effect on a 25000lt pond.

Quote :

I reckon that at best I am getting about 2cm a month on some fish and about 1.5cm on others

1.5 does sound a bit low, 2cm is not great but its not bad either. One of my utsuris that im tracking grows about 2,5cm a month while one of my ogons does about 6cm a month. It went from 15cm - 40cm in 4 months....and they are both in the same pond. Then i also have 2 hariwake/parachino that went from 15cm to 26cm in 5 months thats 4cm per month.

Ernst says he gets about 1-2cm a week from tosai...but i think one has to take the sakai bloodline into considuration cause its been bred to have that type of growth. According to what i have read Sakai tosai are bred to be around 80cm in 3-4 years. Thats an average of 1.25cm a month upto 80cm if you assume the tosai is 20cm.

My feeding schedule. Currently i feed 35g per feeding.

Hi,

I grew koi to 70 cm in 4 years in a pond that was only 80cm deep and had a capacity of 18,000 litres. (Not every koi).

Many koi keepers are getting much better growth rates today.

One thing everyone left out was water changes. You will definetly get better growth with regular water changes. The higher the stocking densities the more this applies.

You stocking densities are fine.

Another thing - genetics - not all koi will grow quickly.

Do not dispare - coupled with the growth is maintaining the quality of the fish.

Chris

I was going to mention exactly what Chris mentioned. Here's my opinion:

* Regular fresh water changes.
I had 2 Koi in a 1000l QT tank (they weren't sick, just new arrivals). I changed around 150l every 3rd day and they each grew about 9cm in 2 months.

* Genes
I consider genes to be the most important factor when it comes to koi groth. Some Japanese breed Koi for size and these Koi sometimes grow to 70cm + in only 3 years.

* Stocking densities and water quality.

Hi Quinton, a minimum of a weekly water change must be a given for an expert keeper like yourself. Personally on my new pond I only do a 4-5% water change at any given time but 3 to 4 times a week. Although my pond is only 3 months I have already seen some good growth on some bigger fish.

Hi,

Please help me out ....

How does water hardness affect the growth of koi?

How does hard water decrease growth and soft water increase growth?

Regards,
Chris

Hi Chris, you beter ask your friend Mike Snaden for the more technical details. I just know it from reading these articles but it does seem to be globally accepted.

Mike snaden did an experiment a few years ago where he gave some of his customers tosai that was going to be grown over the 4 year period. The aim was to get his customers to grow koi to 80cm in 4 years...something that is apparently regarded as not possible in the UK without altering the chemistry of the water. There are articles on his site spanning the 4 years with more technical details.
http://www.yumekoi.com/articles

Some quotes from the articles.

Quote :

It is generally accepted in Japan by the
koi industry/breeders, that koi growth is
enhanced in soft, and pure water. Hi
will become thicker, the shine of the
skin (Tsuya) will improve, and last but
not least, the health of the koi will be
stimulated and greatly enhanced,
hence less problems.

Quote :

TDS Total Dissolved Solids
A TDS reading represents anything that
is dissolved in the water being tested.
This includes GH, KH, fish waste,
uneaten food and chemicals. It is often
said that koi will only grow to the size of
the pond, but in truth, the koi will grow
according to the TDS level in the pond.
A heavily stocked pond, with lack of
water maintenance will result in a TDS
level that will continuously escalate,
hence slowing koi growth as they get
older, (consuming more food, and
creating more waste).

http://www.yumekoi.com/images/stories/pdfs/april_2003.pdf

Quote :

Soft water offers great
benefits in terms of growth,
health, and development,
but isn't the 'be all and end
all'. More to the point, hard water
should be looked upon as a
bottleneck, or limiting factor.

http://www.yumekoi.com/images/stories/pdfs/aug_2003.pdf

Quote :

I consider hard
water to be the
‘bottleneck’ of
koi growth, or
limiting factor

http://www.yumekoi.com/images/stories/pdfs/sept_2003.pdf

Thanks gents - the part ni found interesting is that I posed the question on koi bito - they think its insane that i dont have a koi per 2000l - why does our opinion locally differ so much from what they do in the states? Why dont we get Ernst to comment here aswell !I think we are getting just as good growth rates with collectively heavier stocking density.

What do you guys think is optimal in SA?

https://www.youtube.com/watch?v=yUVY-_InxQU

Check this out - David Soon is one of the top koi keepers globally - he has an 80cm pond and grows fish easily in excess of 70 and 80cm. Enjoy the video - really a gem
Q

Quinton, i see the guys on koi-bito as the hobbists at the top end of the hobby and they tend to be a bit ruthless. I think of myself somewhere in the bottom to middel.

I guess it comes down to what you want to achieve. I am happy with kois to be 60-70cm at the momment. If i look at what they pay for ugly tosai then im very glad im not in the states... $500 for a 25cm kohaku that we will pickup here for R300. I think the guys on koi-bito spends alot more money on their koi than us so its more important for them that the koi achieves the maximum of what it can be.....and so they tend to over compensate. The big names on that forum buy koi for over 1 million Rand.

I had the same "argument" with them about the liters of water per koi a year ago.....and in the end the response was.....koi bito is the forum for the serious koi keeper...as their logo says.

WayneB wrote:

"750 gallons per koi" - That sounds a bit extreme. 750 gallons equal = 3375L. Is that correct?

The general rule that i have heard and read in books state that for every 66cm of koi you need 1000L of water. I thought i was doing pretty well with having 2200L per 66cm of koi.

http://www.koi-bito.com/forum/main-forum/9170-please-comment-my-collection-2.html

MikeM wrote:

Wayne, it all depends on what you want to accomplish. With some skill, a person can keep koi in a comparatively modest amount of well-filtered water, if the goal is simply to have attractive living fish. If that is all the person wants (and there is nothing wrong about having that goal), there is no reason to purchase the genetics of a koi that will grow large.

At the other end of the spectrum, there is the person who is focused only on showing. Then, as large an amount of water per koi as possible is best. Among high-end koikeepers, 1,000 gallons per koi is a 'standard rule of thumb'. (With constant trickle of fresh conditioned water at a 10% per day rate, one might push the gallonage down, but why? Their goal is not increasing the quantity of koi, but maximizing the individual koi.) A friend was keeping 9 koi in 12,000+ gallons, with state of the art filtration, pre-conditioned and softened water, constant trickle, daily filter cleaning ... the result was huge GC koi. The mere 70cm koi looked small alongside the 80-90cm gals. [He did break down this year and added a couple of tosai for fun, but it's not likely they will all stay very long.]

WayneB wrote:

Thanks for clearing this up guys. Bobby has some stunning fish but i can tell you if we did not chat on this forum we would not know about the 3800L / koi stocking rate. I can guarentee you that no one in our chapter knows about the water volumes mentioned above or if they know they are not telling anyone and not practising it.

In our koi chapter there are 2 guys that are classified as serious hobbists and they are sitting at 2500L / koi, so that was what i was aiming for.

Interesting -

You can compensate for a lack of depth by providing a current to exercise the koi. Therefore, depth is not a factor in koi growth and you do not HAVE to have a deep pond.

You can compensate for high stocking densities (like all good koi keeprs have in their ponds if they are honest) with substantial water changes and get really good growth. You can also use activated charcoal filters to supplement the system. But with the activated charcoal replenished regularly.

We have much better water than the UK. Tap water in the UK has passed through the kidneys of 7 people before you get to drink it.

There are things many koi keepers do not take into account and simply regurgitate what others are saying. Even the experts on other forums.

I will drop Mike an email ...

Regards,
Chris

Chris, this always puzzles me - I remember an old guy near to where we stay he had a 2000l pond with only two fish. he had no decent filter besides a sand filter and it looked like his water was fairly good. he fed the cheapie pellets from the local store but had to give his fish away every other year as they grew too big - around 65cm. these were normal pond donkeys and not from good genes. hows this possible?

Quote :

We have much better water than the UK. Tap water in the UK has passed through the kidneys of 7 people before you get to drink it.

lol, that sounds nasty.

Quote :

There are things many koi keepers do not take into account and simply regurgitate what others are saying. Even the experts on other forums.

You are right chris but we dont all have the knowledge to really know how to test al the theories and opinions that people have. At some point one has to accept that other more senior people know better or are experts in their field and you have to take their word and learn from it.

QJones wrote:

Thanks gents - the part ni found interesting is that I posed the question on koi bito - they think its insane that i dont have a koi per 2000l - why does our opinion locally differ so much from what they do in the states? Why dont we get Ernst to comment here aswell !I think we are getting just as good growth rates with collectively heavier stocking density.
What do you guys think is optimal in SA?

The goal for my new pond is no less 2,200L per Koi, my current stocking level is 3100L per koi. The growth goes hand in hand with filtration design, turnover rate, water management policy and 2% of body weight feeding schedule. I am not saying that there are not other workable models and examples but this is my goal to grow my bigger koi to the maximum they can be.

Obviously Koi and bloodline's that are known to grow fast will achieve this within bigger stocking levels.

On smaller koi and on a smaller 10, 000L pond I have already achieved very good growth with my Hi Utsuri of 23.5 cm in less than 6 months. In my opinion the turnover rate of more than 3 times per hour and the effect the Bakki Shower has on water quality, plus a matured filter are all factors that made the growth possible.
In this same pond I had very good growth of my bigger Koi at 1000L per Koi until last year when it slowed down to 1cm in 6months and the same Koi grew 2cm in 2 months in my new pond.

QJones wrote:

Chris, this always puzzles me - I remember an old guy near to where we stay he had a 2000l pond with only two fish. he had no decent filter besides a sand filter and it looked like his water was fairly good. he fed the cheapie pellets from the local store but had to give his fish away every other year as they grew too big - around 65cm. these were normal pond donkeys and not from good genes. hows this possible?

This sort of thing fascinates me. It is so interesting to try to find answers. In the case you mention I think there are a number of factors contributing to the growth of the fish that we do not know.

The owner claims he is feeding el cheapo pellets - OK - but what else is he feeding? We can use logic and say we know you need good nutrition to get good growth so where is that nutrition coming from? Is he supplementing the diet of the two fish with something - krill or shrimp perhaps? Maybe he was too scared to mention in front of his wife what he was actually feeding these two koi. Perhaps he was claiming it was cheap and nasty pellets when in reality it was a very good and expensive food!

Then what about the pond itsself and the filter - was there a possible natural source of food in the form of worms or something like that.

We also use logic and say - we know that we need high levels of oxygen - so we deduct that the filter and turnover rates are very good.

What is on the floor of the pond? Soil? Clay? We don't know.

Water changes would be a must in this case. Again a factor we do not know.

Is his measurement of 65cm correct? Or is this just a fishy story and the size is exaggerated? We know that the average koi thinks he has the biggest koi in the world and that a 40cm koi is massive - then he goes to a koi show and cannot believe his eyes.

Koi can get to 60 cm quite easily, its growing koi to 70 and 80 cm that is not so easy. The number of koi above 80 cm are few and far between. You can grow koi to 55 – 60cm in really grotty water – koi are coloured carp. Carp are known as the pigs of the fish world because they eat anything.

So yes it is possible but we do not know all the facts.

Chris

I look at my dads kois, 12 or 14 40cm+ kois in 2500 liters of water. The pond is 40cm deep. But the water is always luke warm. There is a small 5000 liter / hour pump on the pond and two little airstones in the water.

I think heat plays a more important rule than what we think...

At a pond safari in January we saw some big kois i would recon 50cm or so in what i would say is max 800 liters of water. The owner claims that he had the kois since tosai. But something that i have to point out is that he runs a 0.75kw swimming pool pump on a trickle tower filter.

Yes exactly. Chris, by the way the "old guy with big koi" - I saw it first hand and bought two off him at a stage. the 65cm is spot on, and he does feed the nasty red and green numbers - also no airsones only strong current from two pond returns - pond is basically a cement shell
Q

Sorry for saying so but this debate is all aver the place. Are you guys talking about growth for show or garden pond purposes. I can add examples to the debate of growth achieved by garden ponders with real donkeys. Nothing wrong with that if that is what you want to get out of Koi as a hobby.
I would like to see any of these Koi that has been referred to that has luster and skin quality that is required for show purposes.

One often hear that keepers are buying Show Champions and that this is no fun and easy to do. I would also like to see the ponds and long term results of keepers following this method, I suppose if you buy a new champion every year it is possible in the short term.

In my opinion their is no replacement for growth and good quality show Koi than the following. Excellent water quality, a regular pond maintenance plan, lots of aeration, good balanced food, and buying good bloodline Koi. Keepers are regularly referring to mud ponds and nature, whilst we are keeping Koi in a closed environment with daily recycled water.

I am not at this point yet, but is trying to achieve the above to give my Koi the best possible circumstances, to be the best they can be.
You can spend any amount of money on Koi and buy the best that money can buy, should you not follow good Koi Keeping protocol, in my opinion, over time, you will turn your expensive Koi into donkeys.

Keepers tend to look at the successful and regular show winners and brush it off as the keeper who is buying show winners. I my opinion I have yet to see a successful and repetitive show winner with a Koi pond that does not follow good pond practice.

Bobs, I think you are right the two are worlds apart. I have yet to see someone come up with the exact mix and formula for ideal growth. Everyone mentions all the standard things, space, air, food, water conditions, genetics. Love to know the importance of each weighted to overall success. Is genetics 50% of the total? or can having average genetics be compensated for by extraordinary pond-keeping and essentially money? How much of a difference can everything else make make? Is it the Bakki Shower that delivers growth, more than any other component? If the average koi keeper wanted to suddenly enter the big leagues and grow jumbo koi -what would serve him best over the next year - an extra oxygen pump, or Saki Hikari. Growth? We continually serch for the holy grail.

Bobs what do you think the split is on your side interms of weighted contribution to growth?

Volume per fish 30%
Oxygen 10%
Water Quality/Filter effectiveness/Bio media 15%
Food 20%
Pond depth 5%
genetics 20%

I know the whole is greater than the sum of the parts -it must be, as the more you get right the greater the proportionate reward. I'd love to know what weightings you all place on the above in terms of your own success. Ernst, Wayne, etc - also what about some of the big players in Jhb and Durban!

Good point Quinton.
I believe one has to start with the water quality as a platform (TDS) and build the experience from there. Every environment will differ in the experiment, but one has to start somewhere. In my opinion experiments will be useless if one ignores the basics of good water quality as this will effect all parameters.
Good genetics will be wasted in poor water quality. That genetics play a very important role is validated by our Sakai grow and show average.

If anyone has the proportional scientific answer you are looking for my friend, it will be a real blessing for Koi keepers.