Koi dirtier than goldfish...

[crsublette]

However, the fact remains that if I put into the closed system 4oz of food per day as an example, the amount of nitrogen, carbon, hydrogen, etc. in that 4ozs will be in the pond no matter who utilizes it, whether it's digested or wasted.

If no one eats it and it's all wasted, it's still the same amount of N, C, H, etc. in the pond.
If koi eats it, it's still the same amount of N, C, H, etc. in the pond.
If gf eats it, it's still the same amount of N, C, H, etc. in the pond.

So please explain to me, how a koi makes more nitrogen, carbon or hydrogen atoms from a 4oz handful of food than a gf would? A koi can't make more N, C, or H atoms. The number of atoms in that 4oz of food remains the same.

Of course, this is assuming the decomponsition of the chemical bonds in the food and nutrient displacement is the same pre-digestion and post-digestion.

I often wondered how much of the total food nutrient composition is actually pushed through the fish's gills and skin after the food is processed. I would imagine, since nutrients are absorbed to build new or repair cell growth, that this would indicate there is more nutrients consumed by the body than what is actually expelled whereas none, or very little, of the undigested food is actually absorbed into the fish resulting the undigested food releasing more nutrients into the water.

 

[JohnHuff]

One could argue that if the koi grows more, then they are cleaner as organics are being locked up in the fishes' bodies rather than being released into the pond. That's one reason I like algae growth. I can simply net or pull out the algae and by doing so, I'm removing organics from the closed system.

By the way, I don't understand your first paragraph, can you elucidate?

I often wondered how much of the total food nutrient composition is actually pushed through the fish's gills and skin after the food is processed. I would imagine, since nutrients are absorbed to build new or repair cell growth, that this would indicate there is more nutrients consumed by the body than what is actually expelled whereas none, or very little, of the undigested food is actually absorbed into the fish resulting the undigested food releasing more nutrients into the water.

 

[crsublette]

I have wondered this as well sometime ago. John, my findings agree with your positioning, although it might be stated differently.


If time is a constant, which it is not, then 4oz of food fed to a 4" goldfish would likely give the same waste as that of a 4" koi, that is assuming all of it is digested. However, time is not constant.

A koi can grow 3" within a week. A goldfish would not a month, more or less, to grow the same. As the fish age, then differences become even more vast. Average goldfish length is around 12~14", where the occasional rare 15~16". The average koi length is around 28~34", where the occasional rare is somewhere around 36~38".

Would a 36" koi absorb more nutrients out of 4ounces of fish food versus a 12" goldfish? Probably the same since 4 ounces of fish food is not much at all.

Would a 36" koi absorb more nutrients out of 32 ounces of fish food versus a 12" goldfish? There would likely be more undigested food wasted, that pollutes the water, on the goldfish.

If all things are equal, would a 36" koi and 3 goldfish, 12" each, absorb same nutrients out of the fish food? By the folk in aquaculture fish farming, I am told yes.

I am told exercise makes a difference as well in determining on how well fish food is deigested. I would imagine it is easier for goldfish to get more exercise than koi since koi are a bigger fish required more space than a goldish.

Also, protien content of the food and fish species makes a difference. In fish farms, carnivorous fish are fish a much higher protein food, around 60%, where as the omnivore fish only consume food with around 45% protein.


Just alot of "thinking out loud" spitballing here.


It's tough to get a definite answer on it. I tried to find an answer sometime ago, but I never could find any well written article that would thoroughly explain their positioning. I imagine they are out there somewhere, but I haven't found it yet.

 

[crsublette]

One could argue that if the koi grows more, then they are cleaner as organics are being locked up in the fishes' bodies rather than being released into the pond. That's one reason I like algae growth. I can simply net or pull out the algae and by doing so, I'm removing organics from the closed system.

1) By the way, I don't understand your first paragraph, can you elucidate?

Yep, exactly. Although, if everything is considered equal that is food is portioned properly for goldfish and koi, then that would be true for goldfish as well. This is assuming all the fish are consuming their "fair share", which we know in reality is not the case.


1) By the way, I don't understand your first paragraph, can you elucidate?

Due to the fish's "modes of built-in energy" (whatever that would be), I imagine the fish is likely able to break the fish food's electrochemical bonds, into its constituent parts for absorpation, with less burden on the water resources since the fish is already setup to decompose these complex organics whereas the heterotroph bacteria and other water organisms will likely have to extra water chemistry to fuel the decomposition process.

Then again, the water resource cost might be the same except different resources are consumed out of the water and this difference might be important in regards to whether it is more efficent for water borne bacteria/organisms to decompose the food versus the fish's bacteria/organisms to decompose the food.

 

[crsublette]

Due to the girth of koi I have seen, I have never seen a goldfish gain the same girth. This is another indication to me that koi simply consume more food, whether efficiently or not, than goldfish.

I imagine Mucky is more correct in his assumption in what actually happens since I am told koi, which is a bottom feeder species called cyprinus carpio, is more likely to consume more food due to their nature.

Although, John, you might be correct as well in that the organics are more likely to be trapped in the koi's body if all things, food proportion and total fish inches, are equal.

 

[crsublette]

Personally, I have not found the debate settled yet either way.


I think the crux will come down to quality of food. Do carnivorous fish, that is consuming 60% protein food, produce more complex pollution than omnivore fish, that is consuming 45% protein food ?? Can goldfish consume the same food quality as koi ?? Does higher food quality create more complex pollution? If the koi can consume 42% protein food, where as the goldfish can not, does this indicate the poluttion might be higher?

Heh, I don't know. It would be a fund experiment!!

 

[dieselplower]

I did some reading and I still do t think goldfish have a stomach.

 

[Dave 54]

The koi pond if you look at things is designed for these loads by whatever form of filtration that runs it be that multi chambered, bead, Nexus etc
The turn over of our own bottom drained, vortex/multi chambered filtration system enables it to do so.
Ammonia is leached out by the zeolite, the Nitrite broken down by beneficial bacteria growing on an absulutely humongus area, when taking in the Jap matting which is put together in a portculis type structure to allow clear flow between each individual sheet which are coated with beneficial bacteria,each has three large airstones to allow for de-nitratfication then the huge surface area of the bio filter generated by 6 airstone contaning K1 two differing types of Bio Balls and bio chips makes for the smooth runing of our pond.
The spindrifter/bubbler/bottom drain cover moves the pond in a outwards then down movement towards the bottom drain helping with the disposal of detritus, ensuring a clean pond.
There is a very thin coating of algae in the pond but only down the sides and bottom of the pond and never have the growth of blanket weed that ponds with a high nitrate problem suffer from.
All meals are messured out prior to feeding and we never really see many problems.....
Maintenance is done on a regular basis, as are water changes with each filter being cleaned late spring, mid summer, and late autumn.
For shade we utilize a parasol/sail or pagoda instead of plants
The Zeolite is recharged back to back so there is always a fully charged zeolite at work in the pond.
I think this is the main difference between a formal koi pond and a ponders pond, we are in actual fact poles apart in how we approach and what we do but have the same love of koi/goldfish.







rgrds

dave