Dietary needs of panaques...

featherback · Post by **featherback** » 15 Jul 2007, 13:43

First, the reason I ask this question is, I have an ever growing collection of panaques, and the obsession of understanding them is huge. Even though I have not had much problem feeding them as they mostly just eat wood. I offer some green now and then, plus the occasionally algae wafers. This seems to work, and I know that panaques almost exclusively eat wood in nature. However, I like the idea of feeding them greens and wafers while they are settling in and building up strength after the stress (and often abuse) of transport. I got a 25cm L330 about a month ago and it began to eat wood on day one, but it still does not show any interest in any of the varieties of greens I have offered.
It seems like they learn, through what looks like random foraging that they like veggies. Often this takes a few weeks. My guess is that fallen fruits are scarce in panaque-land, especially deep where the big ones live. And it is probably not an important part of their diet at all. It does seem like they do not seek out veggies or fruits by instinct, like some other fish does.

As I see it there are two answers to this: I offer the wrong greens. I could offer a fruit that actually does regularly fall into (and sink to the bottom of) South American rivers (If there is such a thing). Maybe I would get the desired reaction and I could ‘fatten the up from day one’.
Or the problem is non-existing as the panaques diet is 99% wood, and that’s what it should be in captivity too, greens might not do it any good. Sometimes I am under the impression that veggies ‘flush’ their intestines, and that can’t be good.

This bothers me, so if anyone has any thoughts please post. And hints to which fruits could fall in to the previously mentioned category would be much appreciated. It would be really nice to be able to offer something that the fish accepted right away; it would help all newly imported panaques a lot.

Post by **Shane** » 15 Jul 2007, 17:02

There have been a couple of studies and the answer is that, in the wild, Panaque spp. eat pretty much only wood. There was another paper the experimented with feeding one tank of Panaque (maccus, in this experiment)only wood and another tank veggies. The wood fed panaques out grew or were as big as (in mass) those fed veggies.
Recent studies on the type of wood consumed shows that they are not eating primarily hardwoods (like we mostly use in our tanks as driftwood) but palm trunks. One could certainly give old palm trunks a try although I do not remember seeing any palm trees in Oslo. If you do not have a lot of dead palm trees around you could try canned heart of palm. The only additional info I have is from P. cochliodon collectors who set their traps for these fish with manioc.
-Shane

Bas Pels · Post by **Bas Pels** » 15 Jul 2007, 18:02

Obviously, pinewood is not palm wood, but could it not help out? it is a lot softer than hard wood (and as it is eaten anyway, it will not spoil the water)

MatsP · Post by **MatsP** » 15 Jul 2007, 18:42

Yes, any soft wood is fine. I've got willow and alnus in my P. maccus tank, along with some bamboo that is very clearly eaten - since it's gone from several millimeters thick to paper-thin - with scrape-marks where the fish has recently been eating on it.

--
Mats

featherback · Post by **featherback** » 15 Jul 2007, 21:17

Hi, thank you all for answering.

Excellent info Shane.

My tanks are filled to the brim with what is sometimes sold as 'malaysian hardwood', which probably is mahogany or teak. (Hopefully a bi product of legal plantations). It does not seem to be a problem for the fish to eat these hard woods but I have added some dried out pieces of soft pine to tanks with new fish.

I will definately try to find some natural canned heart of palm tomorrow.
I know that uncooked manioc contains a toxin called cyanogenic glucoside (or something) not very different from cyanide I think. Do you know if anyone has ever tried offering this?

-F

Chrysichthys · Post by **Chrysichthys** » 16 Jul 2007, 14:06

The term is cyanogenic glycoside and you wouldn't want to feed your plecos (or yourself) on anything that might contain it (e.g apricot kernels or bitter almonds) because it releases hydrogen cyanide during degradation.

racoll · Post by **racoll** » 16 Jul 2007, 14:22

you could try canned heart of palm

I wonder if this is available in UK supermarkets

Or maybe it's sold in West Indian stores

.

MatsP · Post by **MatsP** » 16 Jul 2007, 14:24

I agree with Chrysichthys, don't feed any cyanogenic glycoside to fishes...

Slight excursion on the subject:

The lethal dose of Hydrogen Cyanide is about 0.1g (adult human) [studies say around 1mg / kg bodyweight] - and unless you've got the antidote handy when you ingest the cynide, you probably don't stand much of a chance - death in minutes if not seconds. Also having pure oxygen handy at the time of ingestion/inhalation is advisable - but the best advice is to stay well away.

Of course, the taste/smell of cyanide is VERY strong - which is why a bitter-almond will be enough to flavour a batch of biscuits, and you need something like 40g of bitter almonds to make a lethal dose. You need to eat a lot of macaroons to get the lethal dose!

Now back to discussing the feeding habits.

--
Mats

racoll · Post by **racoll** » 16 Jul 2007, 14:30

Just did a quick search, and they are on the Tesco and Waitrose grocery websites.

I hope they stock them.

If they aren't too soggy, I think my Panaque will love them.

Gozza · Post by **Gozza** » 16 Jul 2007, 23:16

If feeding you plecs dont used wood from coniferous trees like pine it has a mildley poisonous resin also avoid woods like yew and laburnum they are also poisonous. those palm hearts look like they might be worth a shot though, on a side note any one else noticed that since keeping catfish the contents of your cupboards have got a bit more "eclectic"

taksan · Post by **taksan** » 17 Jul 2007, 04:56

Euterpe edulis ......cut them down and chop them up and soak them well ..... this is Panaques natrual food.
Works for me!

featherback · Post by **featherback** » 17 Jul 2007, 09:19

I've had no luck finding heart of palm, Norway is like a wasteland when it comes to products and goods that are a little more 'advanced' than potatoes.

taksan: I read in TFH Magazine that a new study shows that fishes in the L27 group eat Scheelea phalerata, a coconut palm relative. Where did you read/hear that they eat Euterpe edulis, and where do you get it?

Gozza: I hear you. I actually find myself being more concerned with feeding my plecos good quality and varied foods than I am with myself. I think they'll probably out live me

F

Bas Pels · Post by **Bas Pels** » 17 Jul 2007, 11:14

featherback wrote: I think they'll probably out live me

It depends on your age, but, being 40 myself, and not expecting to reach 80, I think some of my fishes (gibby, for instance) might be in the same situation.

Catfish are longlived, and thus a special responasability

Chrysichthys · Post by **Chrysichthys** » 17 Jul 2007, 14:32

racoll wrote:I hope they stock them

I'm sure you could get them (and all sorts of other weird vegetables) in the shops along the Cowley Road. I'll check this weekend. They also have cucumbers at 3 for £1.00 all year long.

Trouble is I don't have any panaques to try them on. I've been thinking about getting a Panaque albomaculatus. This would be a good excuse for it.

I think tinned hearts of palm have added salt; I don't know if that's a worry or not. I've fed my plecos tinned peas, but only ones in unsalted water. Sometimes I give my hoplos bits of canned tuna, but again the unsalted kind.

featherback · Post by **featherback** » 17 Jul 2007, 14:46

Bas Pels: I was refering to the sorry state of my body, and all the crap I eat

Anyway, went to one of the bigger shops and was able to find some canned heart of palm. Ingredients are (in this brand;Avila): Heart of palm (obviously), water, salt, Citric acid E330, Anti-oxidant E300.
It has a quite strong undecribable smell, fist time with I'm near heart of palm.

Anyway, I have put one of the stalks in water for soaking to delute the salt++. I am not sure if I have the guts to try it, I'll have to wait and see how the soked one comes out. The smell is very strange

F

racoll · Post by **racoll** » 17 Jul 2007, 15:12

I'm sure you could get them (and all sorts of other weird vegetables) in the shops along the Cowley Road

Yes, the Cowley road did spring to my mind as well.

I think tinned hearts of palm have added salt; I don't know if that's a worry or not. I've fed my pl*cos tinned peas, but only ones in unsalted water.

I feed my plecs tinned broad beans a lot. I used to buy unsalted, but now I can only find salted.

I was a bit worried at first, but they eat them and the fish seem okay.

I'll have to wait and see how the soked one comes out. The smell is very strange

How soft are they featherback?

I was worried that they might break up in the water too easily.

featherback · Post by **featherback** » 17 Jul 2007, 15:20

I would say they are as soft as cooked carrots, but not as strong. The bigger stalks seem to consist of layers which easily smolder. The smaller stalks are in one piece and stronger. I think it will be ok, if I feed small amounts and they eat it relatively fast.

Chrysichthys · Post by **Chrysichthys** » 17 Jul 2007, 15:35

featherback wrote:I am not sure if I have the guts to try it

Maybe you had better test it on yourself first....

This thread started me wondering about artichoke hearts. They contain a carbohydrate called inulin. It's best known (in humans) for causing flatulence, but I would bet that panaques could digest it.

featherback · Post by **featherback** » 17 Jul 2007, 16:16

Well, I had a taste, and it diden't seem that strong in taste, so I tried to offer a small piece. I fed it to one of the larger ones. She(?) definately liked the smell of it, because she became all frantic. Maybe we're on to something here, but I'd be as ease if it was more of a natural product.
Also, the other fish loved it.

Here's vid:
http://youtube.com/watch?v=RlyXfri9dH8

Some pics:

[img:800:602]http://menarana.googlepages.com/PC3.jpg[/img]
[img:800:602]http://menarana.googlepages.com/PC4.jpg[/img]

racoll · Post by **racoll** » 17 Jul 2007, 16:30

I've never seen her try to eat something that fast. Maybe we're on to something here

Excellent. I think we have Shane to thank for this....

but I'd be as ease if it was more of a natural product.

I think it's fine to be honest. Any dried fish food is full of those acidity regulators and antioxidants, and salt is about as natural as you can get.

I'm looking forward to giving it a try.

Post by **Shane** » 17 Jul 2007, 18:29

I know that uncooked manioc contains a toxin called cyanogenic glucoside (or something) not very different from cyanide I think.

I guess this was my bad. I assumed everyone was familiar with yuca (aka manioc, aka cassava) and would know the difference between sweet yuca and bitter yuca. The collectors were clearly not using bitter yuca. That would kind of defeat the purpose. In Venezuela you can choose between french fries and yuca fries at McDonalds.

I am also surprised by how "exotic" of food people find palm hearts. They are delicious and a very common food in South America. Cut them in to small rounds and add them to the next salad you make. I am craving some now...
-Shane

apistomaster · Post by **apistomaster** » 17 Jul 2007, 18:35

I think that because the preservatives in canned foods have been found safe for human consumption then they are safe enough for fishes. Commercial fish foods contain preservatives. I take the same approach as this old quote from Grace Slick, of The Jefferson Airplane, "I don't care if there are chemicals in it as long as my lettuce is crisp."

Chrysichthys · Post by **Chrysichthys** » 18 Jul 2007, 10:53

The antioxidant is likely to be ascorbic acid (vitamin C)--nothing but benefit in that. If I can get hold of hearts of palm I'm definitely going to try it on my plecos, having seen that video.

As for exotic vegetables, Shane, anything that isn't peas is considered exotic here. Carrots--what's that?:D

MatsP · Post by **MatsP** » 18 Jul 2007, 16:21

The ingredient list on the Green Giant tin I've just bought at Tesco's:

Hearts of Palm, Water, Salt, Citric Acid and Ascorbic acid. It doesn't specify if it's "L-ascorbic acid", which is the form that we call Vitamin C when it's part of an orange, potato or efervescent tablet. Even if isn't, it's pretty harmless. Citric acid can't be considered bad either. Salt is debatable, but at the levels that it would produce to a 100 liter tank, I'm sure it's fine.

--
Mats

featherback · Post by **featherback** » 18 Jul 2007, 16:36

A small warning, I added a 1 cm peiece to a 1000 liter tank (the tank with the L330 who's ignoring greens) and today the whole room smelled like heart of palm and when I opened the lid to the tank the smell hit me in the face. The piece was gone but probably just disintegrated, the other fish diden't look too happy, so I did a waterchange.

I will be careful from now on, I'll probably make the heat of palm an ingredient in some homemede 'wafers'. I think it might be a little too poweful 'undeluted'. Plus the wife is not too happy with the smell in the fridge

racoll · Post by **racoll** » 18 Jul 2007, 18:11

the Green Giant tin I've just bought at Tesco's:

I got some today too.

I bet the supermarket stock guys are wondering what the 2000% increase in palm heart sales is all about....

Post by **Shane** » 18 Jul 2007, 18:36

I bet the supermarket stock guys are wondering what the 2000% increase in palm heart sales is all about....

LOL! I am wondering if the canned stuff is a bit different as it is pre-soaked or "pickled." I have had the pickled variety sold in cans and enjoy it and I am sure it is fine for fishes. Better yet, just buy a section of fresh palm heart if available. I realize the "greens" section in Europe is not so big (heck, Jools gets excited about corn on the cob when he visits), but while in the UK recently I was impressed by the variety of tropical foods available.

Just as a side note... one time on the Orinoco I ran into a guy that had a canoe overflowing with freshly harvested heart of palm fresh from the jungle. I bought a section about an inch in diameter and two feet long and ate it for lunch. I still think about how good it was.
-Shane

featherback · Post by **featherback** » 18 Jul 2007, 20:54

I bet the supermarket stock guys are wondering what the 2000% increase in palm heart sales is all about....

hehe! good one. I had similar thoughts when I got a strange look from the lady at the food shop.

taksan · Post by **taksan** » 19 Jul 2007, 08:12

I tried the canned heart of palm.

No luck with the 27's or 330's they wouldn't touch it.

BUT

The 203c/LDA65 titanics loved it.

Bizzare !!!!!

pleco_breeder · Post by **pleco_breeder** » 25 Jul 2007, 06:11

Hello,

All this talk of palms has me curious of what can be substitued from North America. I've looked at living in Arizona as a "fish curse", but realize that I'm surrounded by various palm trees. It would be rather easy to come across a truckload of most any species kept ornamentally or for agriculture purposes.

I'm also curious of what yuca is. There is a group of plants native to the southwest known as yucca that can be grown rather easily from seed. I'm curious if this may be the same family of plants with a geographical spelling difference.

Larry Vires