Aquatic v terrestrial

[esoxlucius]

Slowly but surely i've started cutting out fruit and veg from my fishes diet. I'm not particularly happy doing this because they love nothing more than sliced, diced, or chopped broccoli, sprouts, cabbage, strawberries, raspberries, blueberries to name just a few. The problem I have is that although they wolf it down, within a few hours my filters are clogged with mushed up greenery that they've shat out!

The question I keep asking myself is, how much nutrient and goodness are my fish actually absorbing from these foods when they don't seem to hold much of it in. In the wild they wouldn't get such foods, only aquatic plant matter to graze on. Is part of the problem that a fishes intestines simply cannot process much of the terrestrial based plant matter, for whatever reason? We know that terrestrial meats aren't good for them but yet we are encouraged to feed terrestrial fruit and veg.

 

[tlindsey]

Slowly but surely i've started cutting out fruit and veg from my fishes diet. I'm not particularly happy doing this because they love nothing more than sliced, diced, or chopped broccoli, sprouts, cabbage, strawberries, raspberries, blueberries to name just a few. The problem I have is that although they wolf it down, within a few hours my filters are clogged with mushed up greenery that they've shat out!

The question I keep asking myself is, how much nutrient and goodness are my fish actually absorbing from these foods when they don't seem to hold much of it in. In the wild they wouldn't get such foods, only aquatic plant matter to graze on. Is part of the problem that a fishes intestines simply cannot process much of the terrestrial based plant matter, for whatever reason? We know that terrestrial meats aren't good for them but yet we are encouraged to feed terrestrial fruit and veg.

Very good question
RD.
duanes

 

[duanes]

For a while, I kept a number of truly vegetarian species, (Cincelichthys bocourti and pearsei to name a couple) and those are known to munch on a lot of terrestrial plants.
I found I had to vacuum the substrate a few hours after every feeding, and the next day, so it just became part of my norm.
Beyond nutrients, it seemed with their long digestive tracts, they needed the fiber ( just as we humans do) to maintain health.
With less vegan species, I found a pellet high in Spirulina and other plant products was sufficient.
What species are you concerned about?

 

[esoxlucius]

For a while, I kept a number of truly vegetarian species, (Cincelichthys bocourti and pearsei to name a couple) and those are known to munch on a lot of terrestrial plants.
I found I had to vacuum the substrate a few hours after every feeding, and the next day, so it just became part of my norm.
Beyond nutrients, it seemed with their long digestive tracts, they needed the fiber ( just as we humans do) to maintain health.
With less vegan species, I found a pellet high in Spirulina and other plant products was sufficient.
What species are you concerned about?

My giant gourami is the biggest consumer of greenery and, because of the mass of the fish, the main culprit of the aftermath. He does love algae wafers too and these don't cause a mess afterwards so the benefits of plant based pellets/wafers are already outweighing the fruit and veg option.

I was wondering if it could be anything to do with vitamin C or something else in high levels in fruit and veg which means the passage of food through their digestive tract is rapid, and messy.

 

[duanes]

I had a trio of those true giant gourami's decades back, and agree, mine would down an entire head fo romaine lettuce at a sitting,
or a half pound of thawed peas leaving the partially digested pea shells everywhere.
They were also the type fish I had to do daily vacuuming for.
Soaking the pellets in ascorbic might help, I couldn't get away from the fresh stuff for them.

 

[MrsE88]

For a giant Gourami specifically, wouldn’t feeding fruit that grows natively along the rivers be beneficial even if it runs though them?
Perhaps the “clean out” of their digestive tract is natural and necessary to keep their gut healthy?

 

[RD.]

We know that terrestrial meats aren't good for them but yet we are encouraged to feed terrestrial fruit and veg.

I have strongly discouraged the use of terrestrial based plant matter for a few decades now, and have always supported the use of aquatic based plant matter. I posted the following, or something similar, numerous times on MFK over the years...….

Science has proven that at least with most species of fish studied to date, terrestrial based plant matter can potentially cause health issues, especially if fed in a raw unprocessed state, due to the anti-nutritional matter found in the vast majority of terrestrial based plants. Not a major problem if one is feeding limited quantities, but can cause some serious problems in at least some species of fish when fed at higher levels on a regular basis.


“The presence of endogenous anti-nutritional factors within plant feedstuffs is believed to be the largest single factor limiting their use within compounded animal and fish feeds at high dietary levels. Table 11 summarizes the major groups of anti-nutritional factors present in plant feedstuffs with more specific examples given in Table 12. Although these factors vary in their individual toxicity to fish, a large proportion of them can be destroyed or inactivated by heat treatment processes (Tacon & Jackson, 1985).

Unfortunately toxicological studies have not been performed on the majority of these anti-nutritional factors; on a general basis however their presence in untreated foodstuffs normally results in anorexia, reduced growth and poor feed efficiency when used at high dietary concentrations. For review see NRC (1983), Hendricks & Bailey (1989) and Lovell (1989). “


http://www.fao.org/docrep/003/t0700e/T0700E06.htm


Peas contain phytic acid, tannins, and trypsin inhibitors (anti-nutritional matter) which can potentially cause negative health issues when fed in excess. Check out the list in the link above & be informed, not all plant matter is going to offer a nutrient boost for fish. Just because it's green, doesn't mean that it's a health food for fish.

If one is wanting to increase the amount of plant matter in their fishes diet, my advice has always been to offer fish aquatic based plant matter. The fact that a fish enjoys eating something, doesn't necessarily mean that it's good for them.


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Personally I am a big supporter of feeding aquatic based plant matter, to those species that require it. IMO, NLS makes one of the best commercial formulas available, in their AlgaeMax formula. The GG below was raised by a friend, primarily fed NLS Algae based food. I don't believe that he ever fed fresh veggies, for the exact reason that you describe.

 

[esoxlucius]

I have strongly discouraged the use of terrestrial based plant matter for a few decades now, and have always supported the use of aquatic based plant matter. I posted the following, or something similar, numerous times on MFK over the years...….

Science has proven that at least with most species of fish studied to date, terrestrial based plant matter can potentially cause health issues, especially if fed in a raw unprocessed state, due to the anti-nutritional matter found in the vast majority of terrestrial based plants. Not a major problem if one is feeding limited quantities, but can cause some serious problems in at least some species of fish when fed at higher levels on a regular basis.


“The presence of endogenous anti-nutritional factors within plant feedstuffs is believed to be the largest single factor limiting their use within compounded animal and fish feeds at high dietary levels. Table 11 summarizes the major groups of anti-nutritional factors present in plant feedstuffs with more specific examples given in Table 12. Although these factors vary in their individual toxicity to fish, a large proportion of them can be destroyed or inactivated by heat treatment processes (Tacon & Jackson, 1985).

Unfortunately toxicological studies have not been performed on the majority of these anti-nutritional factors; on a general basis however their presence in untreated foodstuffs normally results in anorexia, reduced growth and poor feed efficiency when used at high dietary concentrations. For review see NRC (1983), Hendricks & Bailey (1989) and Lovell (1989). “


http://www.fao.org/docrep/003/t0700e/T0700E06.htm


Peas contain phytic acid, tannins, and trypsin inhibitors (anti-nutritional matter) which can potentially cause negative health issues when fed in excess. Check out the list in the link above & be informed, not all plant matter is going to offer a nutrient boost for fish. Just because it's green, doesn't mean that it's a health food for fish.

If one is wanting to increase the amount of plant matter in their fishes diet, my advice has always been to offer fish aquatic based plant matter. The fact that a fish enjoys eating something, doesn't necessarily mean that it's good for them.


...................................................................


Personally I am a big supporter of feeding aquatic based plant matter, to those species that require it. IMO, NLS makes one of the best commercial formulas available, in their AlgaeMax formula. The GG below was raised by a friend, primarily fed NLS Algae based food. I don't believe that he ever fed fresh veggies, for the exact reason that you describe.

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That's great info, thanks for that Neil. Before I even posted i'd pretty much made up my mind that terrestrial fruit and veg is off the menu now, the mess is just too much. Plus not to mention it seems there's no real benefit nutritionally.

Would I be right in saying that the top quality "veggie" pellets/wafers have various types of kelp in them? I've often wondered about what effect, if any, a saltwater plant has on a freshwater fish. Is there no concern at all?

 

[jjohnwm]

I have recently developed an interest in Goodeid livebearers, and have read a lot of conflicting info regarding the use of high- versus low-protein diets. Some sources warn that a high-protein "meaty" diet will cause problems at birthing time because the embryos have grown too large to be easily expelled, resulting in the loss of mother, fry or both. Other sources seem to indicate no problems along these lines. I tend to limit the carnivore-type foodstuffs to only a couple meals a week, with the bulk of their diets being algae-based wafers and flakes. I actually use a lot of a very inexpensive brand of goldfish flake that I chose based upon the fact that it is very low in protein...i.e. by most standards, "poor quality".

Since the fish are small, I have been able to satisfy their requirements by actively encouraging luxuriant growths of duckweed, and even hair algae (Amecas and Skiffias actually love that stuff), both in their tanks and in others from which I harvest it. Haven't used much terrestrial plantstuff.

Many years back, I did own a largish Osphronemus Gourami which ate huge quantities of...well, pretty much anything I offered him. He got plenty of duckweed, Anacharis, guppy grass, etc....lots of Trout Chow...and lots of marine Caulerpa alga! I had saltwater back then, and several tanks produced Caulerpa by the armload. Harvesting it helped with my water quality, and the Gourami went wild for it. Voluminous water changes kept salt levels from building up in his tank. At first I was careful to rinse and then soak the Caulerpa before use; eventually that degraded to just a quick rinse...and pretty soon I was yanking it out of the salt and tossing it into the fresh without a care. This went on for years with no ill effects that I could see. When I moved to a different province, the fish stayed behind with a friend, and was still alive and healthy years later.

I'm looking forward to following this interesting thread.

 

[duanes]

The question I have relating to these type of general studies is what particularfish species did they use to determine whether the plant matter was usable or not.
Is it a blanket observation, assigned to all fish, lumping all omnivores together, without taking into account specialists? One size does not "always" fit all.
Over time there are species that have evolved to make use of terrestrial foods in the form of leaves,, fruit and other such delicacies, where aquatic vegetation is not always available.
Did they use these as subjects, or just the generic omnivores available.
Just as Pacu have evolved to eat fallen seeds, and become major seed dispersers in t South America,
giant gouramis, and Cincelichthys, may be the exceptions to the blanket rule, often seen grazing on overhanging leaves, and on fallen fruit in nature.
Their digestive tracts are much longer compared to most other species, and this may allow for this adaptation.
Below an X-ray of pearsei.

There are also certain marine species that also fit into this evolutionary niche.
While in Mexico for a couple weeks straight, I watched the salt water fish in the photos below, come to this certain tree daily (they are under), to eat drooping leaves.