Fish Growing?

alrights lads just wanna see wat yous think about this

1 wat makes them grow

2 wats the fast way to get them growing (prob is no way)

3 wat can slow growth down and why

sure let see wat ppls views are on this

sean

Valerie really sorry forgot to put this into a topic

sean

No worries - moving it now

Valerie

Water changes, good food and limiting numbers/stocking levels. All of the latter not adhered to will cause slow growth.

Kev

Fish growth and fish growth rates.....depends on:
1. the species of fish;
2. the age of the fish;
3. specific genetic material passed down from parent to offspring;
4. the quality of food (ie nutritional balance);
5. the amount of food;
6. temperature
7. the balance between the food intake and energy expenditure (this is the big one...and takes into account 4,5 and 6 above as well as other things such as oxygen content and other water parameters).

Now...there is also chemical control of growth either from within the fish itself, or from other fish.
The general health of the fish effects growth rate.

It is easy to stunt the growth and growth of a fish.
It is not easy to accelerate the growth rate of a fish, and too fast a growth rate may actually be detrimental.

In the list 1 to 7, it is not a simple matter of an increase in food increases growth, and it is not a simple case of an increase in temperature increases growth rate.........because it is number 7 that is the key.
An increase in temp, for example, may increase growth rate to point but the will be an increased requirement of oxygen and food intake to cope with the increased metabolism.

The whole question can get quite complex. But I'll leave it in bullet points for now (as I have a chinese take-away arriving soon).

ian

I would like to just add to Ians post by saying that fish need their own space to grow. If there are too many fish in a confined area they will be stunted.
Phil.

pkearney wrote:

I would like to just add to Ians post by saying that fish need their own space to grow. If there are too many fish in a confined area they will be stunted.
Phil.

And even more important with younger fish. It's a bit like my chinese curry I've just tucked down me....it won't me grow length ways anymore at my age (but may help me put on a gut).

The reason why crowding stunts growth is manifold....and that is where it all gets complex and convoluted:
one fish may chemically stunt another;
one fish my psychologically stunt another;
one fish may physically stunt another by being better at getting to food (and once that bigger fish is bigger then it can get even more food etc etc);
then we have the case of passive stunting by chemical means either from other fish or from the fish itself the chemicals could be pheromone or metabolite, such as ammonia, based)

That latter bit is why lack of water changes will stunt growth.
It is not true that a fish grows to the size of its tank, but it will tend to grow to the volume of water it experiences.....so increases in regular water changes increases the volume of water the fish experiences within a given time.

Fortunately, freshwater fish growth is not as stunted by excess protein as it is in humans. The body weight of a fish is supported by water, and ammonia is generally excreted by passive diffusion in freshwater fish.
This means that fish do not require such a high amount of carbohydrate to use for the energy to support the fishes body and to aid in the elimination of protein metabolism.
But, as with humans, the quality of protein needs to be such as to support growth so that the protein eaten doesn't simply go to waste and end up helping to poison the fish by having excess ammonia in the water.

If you get excess ammonia in the water or incorrect salinity or incorrect redox or incorrect pH then the fish will be expending energy needed to grow on balancing its own internal biochemistry....hence stunting.

If you take a fish such a discus, then, upto the stage of near full growth, a discus needs about 20% of its body weight per day in food: but if you give that amount of food then you need to supply the right temperature and increase oxygen and increase filtration and increases massively the amount of water changes.

In most fish, stunting at an early age will be permanent stunting.

ian

Not to be an Ass but doesn't my reply cover all of the above, I know that I like to know where the keys go to start my Car not what happens after I've turned it, about the direction of current and whether it's ac or dc, surely if you just cover the basics like overcrowding, water quality and the fact that you start with a Fish with a good shape, not over inbred and in good, albeit invisible genetic disposition you'll be on your way to growing on Fry at a reasonable rate?

When Sean goes down the Road of commercial breeding he'll be delighted to know all of the in depth stuff but can we keep it simple for now?

If I am in any way detracting from the Thread Sean , please let me know.

Kev

Kev.

There's nothing wrong or incomplete or incorrect about your reply......the O.P. got 3 different replies addressing more than 3 different aspects.
No one reply here covered everything....and that includes my replies. eg I did not go into the fact that some species of fish require crowding at a certain in their young life else they will be stunted etc etc (I didn't mention that as that would go against most logic...but it is true).

Your reply, stretnik, and pkearney's was on teh question of fish-keeping, and I replied to the question of fish (totally different angles).
That means that the O.P. gets the best of both world for whatever purpose he/she asked the original question (eg for keeping fish, or for breeding fish, or for general info, or for doing an essay in aquaculture)

I do, however, wish that large scale breeders of fish would do their science before embarking on making money by throwing a few fish in a pond.

ian

thanks lads

there seems to be a lot in it and for the main parts its easy enough the right diet and space in the tank (not over stockin)

i asked in the first place as from since i have being fish kipping(only near a year and a half)
i have not had great growth an any species even tho water changes and done on a very week basis (20 to 30%)
diet has been blood worm and flakes and also jbl novo tab and fry it is a mixer off micro worms and chushed flakes in say that i have never had a promlem grow fry on as diet and everything is be work great

although since the last month or two i had to move most off the fish in the main tank as no room in other tanks for them as i had to empty two thanks and it is overstocked and that i think has slowed groeth down a lot but should be all move back in a month or so and now has me thinkin from ians post will this have stunked them or has the growth slowed down

as in when i few them back to there own tank will they grow on?

as off this im thinkin off lettin most off the go for lilttle or nothin just to save the overstockin and also to get them growin on as they should

sean

I'm going to go out on a limb here and say that the flake maybe lacking in some nutritional values, I had this issue a couple of months ago, while feeding flake only my fish wouldn't spawn or even attempt to. I changed my food to nls and haven't looked back. I'm not promoting nls per se as I'm sure similar foods are equally nutritious but it is an all rounder containing many vital ingredients required to promote, growth health and over all well being. While some foods may prevent hunger perhaps that's as far as they go.

Damien wrote:

I'm going to go out on a limb here and say that the flake maybe lacking in some nutritional values, I had this issue a couple of months ago, while feeding flake only my fish wouldn't spawn or even attempt to. I changed my food to nls and haven't looked back. I'm not promoting nls per se as I'm sure similar foods are equally nutritious but it is an all rounder containing many vital ingredients required to promote, growth health and over all well being. While some foods may prevent hunger perhaps that's as far as they go.

you have a kind of point here Damien, some foods are ok to feed fish but like our own foods some are "junk food", a cheap food will not have the same nutritional value as a good quality albiet more expensive food therefore fish will not grow as fast or as well with the cheaper food, but to go back to the main thread, fry / juvies demand a bit more attention in respect to growing them on regular water changes most breeders would do daily water changes on young fish to help them put on size faster, also good foods and live foods of good nutritional value help but expect to feed fry up to 5 or 6 times daily for optimal growth and syphoning out uneaten food which may foul the water, and a big enough tank for them to grow and develop without risk of stunting

thats my 2 cents
Seamus

i like to give them a bix off everything as i should have said in my last reply mix it around for them a bit and they seem to enjoy it i am given them Nls tetra min jbl novo granomix jbl novo tab and also bloodworm and micro worm i think on diet and food wise everything is ok but in sayin that i could be wrong im more to see if the fish will start growing on when i set there own tank back up thanks for the replys lads always welcome and if there more and different food use think i should try out i would be more then welcome to heat

thanks sean

The quality of the food is important....but it is not just the 'brand name' nor the list of goodies either.

Fish need not just the protein etc, but they need the vitamins and minerals in the diet in order to make use of the main ingredients.
If a tub of even the best food is not stored correctly, then some of vitamins etc will be useless.

Variety of foods is the best.

The 'best' ingredient listings by % of protein are not necessarily the best for the fish. What is the best is the 'best balanced' listings.

If going for breeding, it is worth noting that some fish need extra-special care as fry in that either some foods that look great for young will ultimately cause problems when the fish get bigger OR that the fry do not have a proper gut function and need to be fed something elses active guts. !

Fish such as Uaru fry do not grow into even half decent adults unless they have been fed a bacterial-based food such as spirulina; some breeders have reported great initial growth of fry in rift valley cichlids fry fed on brine shrimp but also report that the fry do not make great adults; copepods are vital for some fish when young as some fry do not have a gut function yet use the active enzymes in the guts of copepods....without that initial zap, the fish either don't survive or grow into runts.

If everything about growth and health were simple, then not only would we have 100% cracked fish-health but we would also get our own human species back on track. We are quite a long way off with our own healthy diet knowledge....let's hope we are giving fish something much better than we feed ourselves.

ian

good points made on this topic and would just add that from a breeding and raising viewpoint live or living food is very important at the outset, as the shrimp/worms will be alive till eaten and therefore the chance of pollution of the tank is lessened. however some vegetarian fish such as tropheus will hungrily eat this higher protein food but it will have a bad effect on them as they grow. so with these a spirulina based flake is best and as they are fairly big size and voracious feeders it is easier to see that they eat all food given.
in most cases granular foods are generally better for growth than flake and that gives new life spectrum (various pellet sizes) an edge as it can and will be taken by all fish.