Too much frozen food?

[RD.]

That does at least fall in line with carnivores needing less, and malnutrition shouldn't be an issue since as Stephen St. Clair points out, thee foods are quite hgh in protein.

Keep in mind when one is evaluating foods, and nutrient levels vs quantity etc, frozen foods typically consist of 70%-90% water, which is a non nutrient. Ounce for ounce they cannot be easily compared with dry foods. Dry foods typically consist of 5% water.

As an example......

A typical analysis of freeze dried bloodworms.

Guaranteed Analysis
Min. Crude Protein - 55%
Min. Crude Fat - 3%
Max. Crude Fiber - 5%
Max. Moisture - 5%

A typical analysis of frozen bloodworms. (from the same manufacturer as above)

Guaranteed Analysis
Min. Crude Protein - 6.3%
Min. Crude Fat - 0.8%
Max. Crude Fiber - 0.3%
Max. Moisture - 91.2%

 

[TwoTankAmin]

Here is what I have come to believe about feeding our fish. Work backwards from nature. Species have evolved to thrive on the foods available where they live. To some extent i would suggest those who only keep fish indoors in glass.acrylic boxes have a chat with the filks who do ponds and summer tubbing. Often these are fed minimally since nature provides a lot of food for them naturally.

This is often in conflict with what it takes to create fish foods or to imbue some level of shelf life and how long they can be used once opened. A lot of the ingredients in commercials sticks. wafers and flakes is filler or things needed to hold things in a useful solid form.

My best suggestion to folks re feeding and choice of foods is to read the ingredients. Here are the ingredients for several different forms of blood worms:

Hikari Frozen: Blood Worms, water, vitamin B12 supplement, pyridoxine hydrochloride, L-ascorbyl-2-polyphoshate (stabilized vitamin C), carotene, riboflavin, thiamine mononitrate, biotin, choline chloride, folic acid, calcium pantothenate, inositol, niacin.

Tetra Freeze Dried: Freeze-Dried Blood Worms (Insect Larvae) Only.

Kensfish premium Bloodworm Sticka: Salmon Meal, Soy Flour, Fresh Bloodworms, Wheat, Oat & Gluten Flours, Frozen Or Dried Brine-Shrimp, Dried Spirulina, Lecithin. Fish Oil, Vitamin B1, A & C. Choline Hcl, Biotin, Methionine. Thiamine ( Source Of Vitamin B1), Asorbic Acid (Source Of Vitamin C ). Dried Bacillus Subtilis Fermentation Product, Dried Bacillus Licheniformis Fermentation

My personal opinion is that many of the commercial foods may be adequate but they are also not near the top of the list for feeding. The best foods are live and/or fresh. This is especially true for those who are breeding their fish. The next best would be frozen version of these. After that my choice are the Repashy Gel Mixes. Finally, I do feed commercial but I try to limit it to 15% of the diet.

The other side of the feeding coin (not the nutrition side) is the cost to feed and the effort needed to feed. To feed Repashy to all my tanks takes me about 30 minutes. To feed frozen to all my tanks take 15 -20 (prep time is longest for thiese foods). To feed commercial flakes and sticks takes me about 10 minutes. It is easy to find myself feeding too much commercial because of the time factor involved.

I do not feed every tank daily. The exception is tanks with young fry.

 

[RD.]

I posted the following here many years ago ......

To be honest, from a nutritional aspect the average hobbyist typically has no idea what the exact nutrient levels are of the various raw foods that they feed their fish, or how each species will assimilate those various nutrients. You can't simply feed a fish that in the wild is predominantly a frugivore, such as Heros efasciatus, slices of apples & oranges, and assume that this is in any way a more natural form of food for the fish, than a well balanced pellet. In the wild a frugivore will seek out the fruits & seeds that contain the highest level of protein/fat, not the ones that mostly consist of starch. Add to that the nutrient requirements of most species change as they mature, so what might be ideal for a fry/juvenile, could be (and often is) completely different compared to a mature individual.

The reality is, for the vast majority of ornamental species of fish no one (including myself) has the slightest clue what the optimum dietary requirements are, as the vast majority of these fish have never been studied long term with regards to dietary requirements. Most haven't been studied on even a short term basis. You might be able to mimic a fishes natural feeding behaviour by feeding live foods, but most hobbyists will never mimic the seasonal variations of a natural diet that take place in the wild. Raising your own live bearers, fresh water shrimp, crickets, and worms generally won't even come close to matching what a cichlid in the wild consumes on a regular basis. The nutrient profile of each foodstuff is dependent on what each of those foodstuffs in turn consumes, which in captivity is usually nothing remotely close to what those live fish, insects, crustaceans, nymphs & worms would consume in the wild.

This is why if one refers to the nutrient profile of say an earthworm, one can only ball park that data as the protein/fat/mineral content will be entirely based on the environment of where that worm originated, as in what that worm consumes on a regular basis.

So comparing terrestrial based plant matter, vegetables. fruits, etc on a whole is only a guessing game, as for the most part the only raw ingredients that have been closely evaluated by men of science over the past 100 years are those that are primarily grain based, and only involving species of fish that are raised for human consumption. And most of that data is based on short term feed trials, as most of those fish aren't destined to become family pets - they are destined for a barbecue.

 

[MultipleTankSyndrome]

RD and TwoTankAmin, thank you for sharing all of this data. Certainly is something to contemplate and is very comprehensive as well.

I'll report back when, going off of that data, I can get a ballpark idea of how much of what to feed based on the ingredients in the specific products available to me.

 

[MultipleTankSyndrome]

Finally got the chance to analyze all the nutrition in the frozen/dry foods available to me (expanded to include daphnia, krill, and zooplankton in addition to everything listed above).

Taking protein and fat as proxies for the nutrition my fish would get in the wild (since as carnivores/molluscivores/insectivores they'd need those as their nutrients), the bloodworms, mussels, mysis shrimp, brine shrimp, tubifex worms, daphnia, krill, and zooplankton average out to roughly 7%. Meanwhile, the pellets and flakes average out to 56.3%, both with relatively minimal scatter from that mean.

While this is certainly very rough as a guess for the reasons pointed out above concerning just what wild fish eat, I'd have to feed roughly 8 times as much of the frozen food compared to the pellets/flakes. That is, regardless of how much and how often I feed my fish, 8 meals of frozen food per meal of pellets or flakes.

It also falls in line with TwoTankAmin's suggestion to limit the processed food - I find myself agreeing with this given that they have a surprisng amount of filler and are considerably further from the state of the food the fish would eat in the wild compared to the frozen food.