Feeding Large Predators, Please Read

[EdKruzel]

There are a few of us on here that continuously repeat ourselves on the danger of feeding FW (goldfish, guppies, mollies) to marine livestock.

It is a very important issue towards the long term well being to the animals you keep.
This link is a very good article on the subject written by Ph.D. Rob Toonen.

Section 2 covers live feeders.

The only portion I disagree with is where he mentions hand feeding. Use a feeding stick or other artificial feeding apparatus.

http://www.advancedaquarist.com/issues/dec2003/invert.htm

Enjoy,
Ed

 

[billsreef]

A good article. Worthy of being a sticky. Though I do have to wonder what Rob was thinking about when talking about feeding lions by hand :eek2:

 

[M.Dandaneau]

The only fault I can find with the article is in relation to using mollies as feeders, even though I do agree with the author in relation to brackish feeders tending to be similar to freshwater feeders as far as lack of elements and additional fats are concerned.

If fed straight from the LFS, then I agree fully, but I often advise people to introduce a small school into a marine aquarium, particularly with juvenile lionfish/scopionfish specimens in an established aquarium or species tank.

My point of contention is that, unlike guppies, mollies are largely vegetarian by nature and are often full of phytoplankton and algae by the time they are consumed, just as are the intestinal tracts of most wild feeder fish, thus the point of balance in the diet.

While I've not seen any scientific reference in literature, I've also pointed out that many to most "frozen" feeders in LFS are silversides and other easliy trawled open water species, whereas the bulk of the diet in the wild for most marine reef predators rarely, if ever, contains any of these, being comprised instead of less fatty species, such as damselfish and grunts.

Mike

 

[Fin Follower ED]

great artical, and good name

ED

 

[Fin Follower ED]

great artical, and good name

ED

 

[jjp2121]

Unintentional live feeding

Unintentional live feeding

I have a 125 with a medium lime wrasse, small Huma, medium blue angel, blennys, goby, small parrot and a clown. My wife wanted some fish to school together in the tank. The LFS sold us 4 green damsels and said they would be fine. They were fairly small in size, but not smaller than the Blennys.

I looked in the tank a few minutes after release and only saw 3. 15 minutes later I was down to 1. Now there are no damsels to be seen. I don't think damsels hide??

Who is the culprit? Does this mean that I cannot add any more small fish to the tank or are the damsels just helpless? Is the culprit going to start picking off other critters?

 

[EdKruzel]

Any and all fish can/will hide if there is an area for them to conceal themselves.

You have several fish capable of taking out chromis and many other small species fish.
Many of the blennies are poisonous and will be left alone.

With the list of fish you have in a 125 I believe you are at your max.
You have to think long term and the adult sizes when stocking.
The Huma will only reach the 9'' range but claim a fair amount for its territory. A Blue Angel can reach a respectable size for your tank as the Parrot will well exceed a 125.

Research before purchase,
Ed

 

[jjp2121]

I appreciate your thoughts.

 

[M.Dandaneau]

The probable culprit, by the way, is the triggerfish.

In the open water, he's both faster and more maneuverable than the chromis, with teeth that can reduce one to bite sized bits in minutes....combine this with the fact that they tend to get territorial and attack new fish and that makes him stick out of the line up, like Jack the Ripper mixed in with the Backstreet Boys.

Mike

 

[MattScott]

I fed guppies every now and then as a treat, i just set them in saltwater for about a half hour, then take them out and drop them in, that would kill all diseases about to be introduced wouldnt it?

 

[M.Dandaneau]

Guppies ae OK occassionally, but like all FW foods are high in the wrong fats......if you switch to mollies, you can toss them directly into the tank, where they will thrive until eaten and eat some of your alae while waiting.

Mike

 

[popeone]

Now I now that you are not supposed to feed marine livestock feeder fish or freshwater fish. But, I have a breeding tank with guppies that I SLOWLY overtime made it completly saltwater. I did some reading and there is question if the guppie is actually a brackish fish or marine? If it is a marine then wouldn't it be okay to feed to marine livestock?

 

[EdKruzel]

Not necessarily, guppies are ok for treats. Just because they can adapt to brackish or marine does not mean that their body composition will increase to the proper levels of HUFA's.

It is the proper type and not amount of fat that is required by predatory marine species.

If you have a large tank with plenty of rock work, then dump a significant amount of guppies in the tank about once a week.

This is mainly for instinct behavior and exercise more than nutrition.

Take care,
Ed

 

[M.Dandaneau]

Ed brings up a good point here that I've never seen mentioned before.

Many predatory fish will adapt to captivity with little or no problem, eating whatever substitute foods are offered, and the results dependent upon the nutritional combination needed by that particular fish or species, but this doesn't take into account hunting instinct and the need to be what they have been molded into by evolution.

While it may be apples and oranges, three developments over the past few years do have some interesting implications:
1) Golden Lion Marmosets were once considered impossible to keep in captivity, until it was found the animals were dying from protein starvation from immaculately clean fruits and vegetables...in the wild, their food was riddled with fruit fly maggots and such which had become an essential part of diet.
2) Many snakes that had been deemed impossible to breed in captivity were found to be bored! Researchers were startled to discover that if two males were placed in with a female that was previously ignored, they would fight over her, with the victor claiming mating rights......who says jealousy is a purely destructive emotion? **grin**
And lastly, 3) Cheetahs were often notoriously hard to breed until it was discovered that inactivity seemed to be the missing link in the situation.......one of the national zoos has now started treating their cats to snacks on a line that zoom across the enclosure and have to be chased, much like the mechanical rabbits at a greyhound track and has reported a sharp rise in the fertility and mating activity of their animals.

The bottom line is that although proper nutrition has to be achieved for the successful rearing and maintenance of many species, it's beginning to become evident that when we try to make something into something it isn't supposed to be, we may be creating glitches that we simply haven't foreseen.
While freshwater fish aren't a good basic diet, there may be more worth in feeding them live treats than was previously realized, particularly in species where captive breeding is desired.

Our ability to supply live marine feeders may have much more to do with our lionfish breeding than I previously realized.

Mike

 

[EdKruzel]

Thanks for the words Mike,
I may not have many degrees hanging on my wall, however I do have more than 20yrs of field experience working with animals and keeping our aquarium friends.

From just maintaining large reptiles, birds of prey or training the many animals I've worked; the constant denominator has always been to utilize their natural abilities and instincts.

Currently I work one of the best Narcotic Detector Dogs out there.
He has buried his competition time and time again. I know I am a good handler and would love to claim success for his accomplishments, but I can't. The dog is a natural and our training regime utilizes his natural instincts to hunt and kill. The modification is to allow him to hunt for the odor of narcotics and allow him to "kill" and posses his reward toy.

With this dog it's a manipulation for the purpose or need to fulfill a human task. With fish it is the same principal without the human need.
I refuse to keep a fish or invert to which I cannot provide a natural environment.

For anyone that doesn't know Mike and the wonderful location he has, you should check out some of his tanks and threads about the various systems he keeps.

Take care,
Ed

 

[M.Dandaneau]

Darn Ed....now you made my hats too small.....sheesh.

If you're ever down our way, pets and wildlife are always welcome too!

Mike

 

[speek]

so would u guys say gutloaded(i do cyclopeeze and selcon) ghost shrimp is a good staple diet for large predators?

 

[M.Dandaneau]

Actually, no...........live marine shrimp are the preferred food (depending on the species being kept, of course....a piscevorious species may prefer or be specialized for fish rather than crustaceans, so knowing as much as you can about each individual species that you have or intend to keep is a big assist)

In cases where you have smaller predatory species that refuse all but living food, gut loaded pet shop ghosties may be the best you have to make do with until you can train your specimen over to frozen seafood pieces that will give it a more nutritious and varied diet.

Here in Florida, ghost shrimp occur naturally in all naturally ocurring environments, fresh, brackish and marine, and I suspect that some may be the same species that can slowly adapt, but that's not something that I know for certain, just an educated guess.

Likewise, I suspect gut loaded mollies, also a brackish water species, may serve as a temporary food for finicky species that initally demand live food only.....the predator gets the food value of the shrimp or the molly, plus the food value of a good marine flake that's in the system as well, not perfect, but better by far than just freshwater feeders.

Mike

 

[speek]

i have stonefish(i know about the poison etc i have done my reasearch) i also feed them damsels but was thinking this was a more economical way i was still gonna offer damsels occasionally and i feed them this yesterday and they loved it

 

[M.Dandaneau]

As Ed pointed out, by living here in Florida,I (and anyone else living along either coast) am much more fortunate than most.....as the article points out, the vitamins and minerals in freshwater organisms simply can't supply a balanced diet sufficient for most marine creatures.

The biggest thing to keep in mind is that MOST of these fish don't have to have a diet of nothing but live fish, and if you start thinking "outside the box" (or "outside the pet shop") you can end up with a much better diet for far less than people realize.

The frozen seafood section of any good supermarket offers fish, shellfish and crustaceans for human consumption, which SEEMS expensive, but if you take a pound of fresh shellfish or fish, cut it up into suitable sized pieces and freeze it into baggies that can be thawed out for, say 3 days at a time, you've got a good diet that can go a lot further than many prepared foods.

A strip of fish flesh, impaled on the end of a plastic feeding stick, can be waved to entice the majority of predatory species and go a long ways.

Mike