Acestridium dichromum

[lurch1000]

I just got off the phone to Nick about something else, wish I'd seen this before I'd called.

Teeth are rather special, wonder if they're for helping latch on better in turbulent water as much as they are for eating?

Oddly enough, my Otos won't eat courgette, blanched or boiled to hell, they prefer the glass algae, especially the GSA which amazed me. I've had many people tell me I need to clean it all off, but I won't remove a food of choice of a fish. Bit off the point, but it may be that whatever is living on your glass is way tastier than vegetables.

Wonder if fruits would be suited to those teeth at all, or too sugary?

[MatsP]

As long as you try with only a small amount of fruit, I don't see a problem. I've fed Ancistrus with Mango with great success (and you can see when they eat it, as you get yellow/orange "sausages" in the tank!)

--
Mats

[Jools]

I don't know about fruit, I'd be very surprised to find small river fishes specialised to eat fruit - especially from the inside out. I think we're over cooking this thing, the fish is fragile, it appears pretty specialised, but it's not that different from a small

Farlowella

. I suspect breeders of that genus would be pretty good at them. All things considered, it's probably this diminutive fishes journey from river to tank that makes it a hard species rather than an elusive set of water requirements.

I'm not confident about them, but I'm just going to keep an eye on water, methodically try some veg and a few types of smaller frozen food and see what happens. I have lost one already (yesterday), it was the thinnest.

Jools

[lurch1000]

That's a real shame Jools. Gutted to hear that. Bit of luck, that'll be the only one.

I see what you say about the water, but I'm torn between just clean fresh tap water or going more acidic blackwater now. All stems from looking at some of the general location data I have really, and a pH^ of 6.6 would be the highest pH for these fish from what I can tell so far. Just by adding oak bark to my water I can drop the pH and TDS of the body of water, but it really throws in the tannins as you'd expect.

Other thoughts on an extremely low pH would be that it would limit or remove the risk of bacterial health issues with the fish, or so is my understanding based on how Parosphromenus* spp. are kept.

^ Acknowledging Darrell's comments on pH at low TDS.

* excuse spelling, usually get it wrong!

[MatsP]

I do agree with Jools that the water conditions aren't likely to be the big problem - yes, they need soft water, but I wouldn't worry at all about pH and I would say that TDS around 100 is fine. Just like Otos, the problem is largely that the travel from capture to "new home" is not great for small grazing fish. In nature, I'm sure, like Otos and Farlowella, they are almost constantly feeding. Similar to some plecos arriving in shops starved and then never eat again, because they're "trapped" in a starvation pattern.

--
Mats

[lurch1000]

Back to that video, on asking some plants bods, they believe that the plant in the vid is a submerged branch of a terrestrial plant, possibly Anona or Guava species.

Not that we could get a steady supply of those to the domestic tank, but the A.dichromum may regularly graze on the micro-critters that dwell on the leaves as part of their diet.

[CoryWally]

I've kept and bred farlowella and sturisoma like many PC members. Both like their fair share of more proteinaceous foods. I'm currently keeping

oxyropsis

, another hypoptopomidae, not unlike Acestridium, which are relishing any all-round tablet foods and baby brine shrimp. Other loricariinae I've kept thrived on bbs. All I'm saying is don't get too hung up on oto types being strictly vegetarian, not many smaller suckermouth catfish refuse the chance to sit on the tank bottom with their noses in the flow sifting brine shrimp nauplii.

Mark.

[lurch1000]

As I've mentioned before, my Otos don't really touch courgette, for veg they prefer algae or what lives in it. Tried Artemia eggs today, 3 of the 4 Otos went mad for them! Other one stayed glued to the E.cordifolius. That's now on the regular menu.

[lurch1000]

Just been looking at your pictures again Jools, Picture 8 really shows up the markings on the fish, amazing detail in those photos.

Furter to my comment about these fellas getting nutrition from leaves of fallen trees/shrubs, or branches that get submerged at times of the stream running high, I wonder if those teeth are used to remove larval cysts or crack open any cocoons or cysts encapsulating larvae and other insect stages undergoing metamorphosis on terrestrial plant leaves? Firmly puts them in the omnivore category if they do.

[Jools]

TDS of the tank is 280 drops to 250 after each water change. I've lost two, probably to starvation I think (not sure as they are so small) but four are still going and two are very green. I am feeding by placing dirty drip trays in front of the filter flow and they have started hanging out there. No positive eating observed.

Jools

[lurch1000]

Hmm, that throws my TDS thoughts off on a bit of a tangent.

Hopefully the remaining healthy looking ones stay with you and healthy. Found some more references to these fish, so I'll start reading up on them.

[dw1305]

Hi all,

As to the silver bullet, I think DO is the key

I'm not sure about silver bullets, but this is the approach I use with all fish. If the fish don't need high oxygen levels it won't effect them adversely, and if they do need high levels of dissolved oxygen you don't get a second chance if you get it wrong.

and, perhaps, keeping them in a established (read dirty) planted tank with decent water quality and current.

Some "biofilm" may help with providing additional food sources, and some DOC helps with water quality and may chelate metals ions etc. <http://www.skepticalaquarist.com/dissolved-organics>, <http://www.skepticalaquarist.com/biofilm> & <http://www.skepticalaquarist.com/maturing-biolfilm>.

but I wouldn't worry at all about pH and I would say that TDS around 100 is fine. Just like Otos, the problem is largely that the travel from capture to "new home" is not great for small grazing fish. In nature, I'm sure, like Otos and Farlowella, they are almost constantly feeding. Similar to some plecos arriving in shops starved and then never eat again, because they're "trapped" in a starvation pattern.

I'm sure this is right.

Back to that video, on asking some plants bods, they believe that the plant in the vid is a submerged branch of a terrestrial plant, possibly Anona or Guava species.

I'm not convinced about this, plants are my "day job", and the growth of algae on the still photosynthetic plant leaves would strongly suggest that it is an aquatic, or used to being flooded (if it is in the flooded forest). I'm pretty sure that the leaves of a terrestrial tree like Custard Apple (Annona spp.) or Guava (Psidium spp.) wouldn't combine being that green with that amount of algal growth.

I had a good look at the teeth of these guys and they are raspers not pads like many other hypoptopomines.

They are interesting, and set in a v like a Panaque.

Lord only knows what they do with them.

I think we are probably all hoping that you find out.

cheers Darrel

[lurch1000]

Hi Darrel,

My thoughts as to the occasional submerging of terrestrial leaves wasn't algal content, but larval content, or maybe insect eggs giving them nutrition they won't get from algal or vegetable matter. While aquatic plants are known for biofilm, there must be a terrestrial equivalent for the microscopic life that lies upon the surface of leaves normally exposed to air.

Thank you for the links, I shall have to pop them open properly when I'm on a suitable device.

[lurch1000]

Great articles Darrel, thank you!

[dw1305]

Hi all,

Great articles

I can't recommend the "Skeptical Aquarist" highly enough, as well as the great content it is so well written that it makes technical subjects accessible. This is a recent post on the role of lower conductivity in triggering spawning <http://www.skepticalaquarist.com/kirschbaum-method>.

There are some more Acestridium dichromum & plant pictures at: <http://www.l-welse.com/reviewpost/showp ... roduct/999>. They don't give enough information to get a more definitive ID for the plant, but you can see the parallel leaf venation, meaning it is a mono-cotyledon, and also some really big tufts of a red algae growing on the leaves, both of which are definitely suggestive of a true aquatic plant.

While aquatic plants are known for biofilm, there must be a terrestrial equivalent for the microscopic life that lies upon the surface of leaves normally exposed to air.

There is, but plants go to great lengths to try and keep their leaf surfaces clean. Because the leaf needs both light and gas exchange (via the transpiration stream through the stomata) for photosynthesis, the evolutionary pressure to develop "stay clean" leaves is strong. In a warm, moist atmosphere (like a rain-forest), nearly all the plants have hair-less glossy leaves with a "drip tip", as ways of shedding water and limiting the growth of lichens, bacteria and fungi that would otherwise coat the leaf's surface.

My thoughts as to the occasional submerging of terrestrial leaves wasn't algal content, but larval content, or maybe insect eggs giving them nutrition they won't get from algal or vegetable matter.

I can see where you are coming from, and the periphyton, aufwuchs or biofilm (all the same thing) will contain an amount of animal protein from rotifers, crustaceans etc as well as cyanobacteria, diatoms, and red & green algae. Loricariid aufwuch feeders typically have a pad of many fine bicuspid (forked) teeth (like velcro) for snagging the the algal threads.

This is why the teeth of A. dichromum are so interesting, they definitely aren't a pad, but are in a V, reduced in number and much more substantial. They have evolved to rasp at something, but what? Thoughts that come to mind are wood (very soft wood? with a high fungal biomass? or possibly the mycorrhizal roots of trees ("Arbuscular mycorrhizal fungi"), freshwater sponges? an encrusting (rather than filamentous) algae. Because we are talking about regions with very high species diversity some species may have evolved very specific and specialised food sources, often one that only they can exploit (Pandas and Bamboo, xylophagous loricariids etc).

Panaque spp., which process sunken wood by rasping, also have a reduced dentition of V shaped teeth, but in this case with a single point. I'm not sure what the teeth of cochliodon group Hypostomus look like (but presumably Panaque like due to convergent evolution) - <http://www.planetcatfish.com/forum/view ... =5&t=27511>.

Other loricariid usually have bicuspid teeth, although they may be reduced and specialised for eating snails, or prising insect larvae out of crevices etc. Post here: <http://www.planetcatfish.com/shanesworl ... cle_id=402>

cheers Darrel

[lurch1000]

As ever, brilliant links, you must have a memory like a sponge to keep on top of where you see this stuff!

[lurch1000]

Something I've just being trying to have a quick scan for, but have nothing so far - any ideas if or how much the water temperature in the natural habitat would vary by depending on rains, weather etc etc?

[lurch1000]

The tank is about ready, few bits to do. The Redmoor needs to hurry the hell up and sink without needing rocks on it!! Then just awaiting the fish.

Any updates youre able to share on yours Jools? No worries if not of course.

[Jools]

Any updates youre able to share on yours Jools?

Nothing much to add really. I've still got three, no idea what they are eating but don't show signs of malnutrition (although it's hard to spot on such small fish). I added a marine white light to the tank yesterday to overcook algae production.

Jools

[lurch1000]

It is a bit hard to tell whena thin fish is thin

It's encouraging that you've had them this long. Obviously eating enough as it's been long enough now to not be running on reserves.

I was in a quandry about light, bright or moderate. I've got a 24W T5 abouve it at the minute that I acquired. The box shows one 3 sides 6500K, 8000K and 10000K. It's not 10n could be 8, but I'm rubbish at telling the difference without something to compare it too. It looks colder than daylight, so the favour of thought is to 8. I'm off to buy some small pebbles to keep in a clear jug on the window sill to catch the sun (read: daylight) and I'll load this water with nutrients to encourage algae and swap stones around between the tank and the jug.

I was in danger of getting carried away with the biotope idea, but I've overcome my irrational obsession with continental plants and putting in ferns. Thanks to Darrel really. Nearly lost sight that this tank is for the fish, not for me.

Thanks Jools.

[lurch1000]

Something I completely forgot about. Put the chaps on ice when they perished. Still there. Barring potential tissue damage, they likely to be of any use for any purpose at all? I suspect not, but best ask the question before disposal...

[Jools]

Thought I'd share a video of my trio. What you see here is the smallest one on the side glass of the tank and then it pans to a dirty (algae and mashed food) drip tray submerged in the tank upon/behind which is the largest fish. Gives a sense of current, DO, brightness and the fact these fish aren't into plants especially, they just like flat surfaces with food on them in serious current. And they're not light shy one iota.

Jools

[lurch1000]

Great clip Jools!

What's your mashed up mixture? I've heard of mixed inconclusive success with these in other quarters for these.

I was beginning to wonder if I'd over done the flow on my tank, but probably not!

[Jools]

Thanks, I had some great suggestions (especially from Pete) around what to feed these guys.

The mashed food is more accident than design. On the (glass) drop trays food such as flake and granules get stuck on over time. So, it's that as well as various hues of algae that they are working through. They don't look hollow bellied(it's hard to tell) but I have seen them defecate, so they appear to be eating something.

Jools

[L-ko]

Hi,

thank you for your information.
A few animals I have since 2.5 weeks.
My experience so far:
There were eight.
One died during transport.
One died shortly after insertion into the new aquarium.
Five it is certainly good. (Seen at the same time.)
In one of them I do not know. (I can at most partially differ in size. But more of them have the same size. ~4 - 6 cm)

They graze the glass of the Aquarium, thin branches and air pipes.
Some respond to JBL Novil fluid.
I get powdered food, which deposits on the glass and so on.

Water Parameters:
pH ~6 - 6.5; conductivity ~ 100 - 200µS/cm; temperature ~27°C









Greetings
Elko

[lurch1000]

Hi Elko,

Thank you for the information! Do you have strong flow in your tank?

Very good pictures you have.

[L-ko]

Hi,

No, I haven't strong flow in my tank, but I have much oxygen there.

Greetings
Elko

[lurch1000]

That kaiboshes one of my theories then!

Making an assumption based on your location, but do you know if your Acestridium dichromum came from Aquarian Glaser at all?

[L-ko]

Hello,

I don´t have Information about the location.
That Aquarium Glaser exported these is possible.

Greetings
Elko

[lurch1000]

Looks like I now have a 2' tank with a change of direction as I can't get these Acestridium any more. No idea what to do with it. Probably need to get a smaller filter for it for starters!