Acestridium dichromum

[lurch1000]

So, more mulling.

Nearly got a 3' 100l, but got the look...

2'4" is the length of the cupboard, so kinda that's it.

Spent the evening considering your last comment Jools. A species tank by definition of course should have one species. Dithers are a consideration, depending on the principal species. Any tank is going to be a considerable space for two Acestridium, so some additional fish would offer better use of the tank.

Whatever happens, be it strictly a species tank or an understocked two species tank, how far should I take the water from how they were kept in the shop? Stop at the mid-high 5s? Keep it a tad above 6 to ensure biological filtration?

Mostly my musings there, but thoughts and opinions welcome.

[lurch1000]

Little piece I found on the Morichales water where I believe Acestridium dichromum has been found previously.

http://www.scielo.org.ve/scielo.php?scr ... so&tlng=es

[lurch1000]

And I have a 2' tank! Picking it up next Saturday.

Very chuffed. Have some water that I'm currently tinkering with to see what comes of it. Going to investigate papwalker's Orinoco Tea as well, see what happens there in my little test pot.

[lurch1000]

I have a 3D backdrop that I've been trying to sell.

Are they worth bothering with for a tank like this?

[pleco_breeder]

I have another specific reading from a collection in 2010 by Nathan Lujan which was temp = 28.6ºC, pH = 5.7, SpCond = 12.7 µS/cm, DO = 82% sat, 6.4 mg/l. That's pretty high DO for warmer water...Jools

Haven't been on for a while, but think I have an idea of what is going on in this case. However, have never kept, or seen live specimens of, this species. I'm simply guessing based on the temp, DO, and pH.

My tanks generally average a DO of 7.0 at 83 F. However, it takes some very specific work to do this, and I think the reason I do that work may be indirectly related to the problem here since it would be very difficult (if not impossible) in a heavily planted tank. I've noticed in fry and "sensitive species" tanks it's very important to wipe down the walls and all ornaments/decorations/caves on a regular basis. I do this in order to limit BOD in the tanks. However, in the case of sensitive adults which are notoriously difficult to maintain this shouldn't be as important as long as good DO is maintained. That just doesn't seem to be the case though. I've theorized a range from a lack of proper food due to bacterial competition for substrate to grow through a direct sensitivity to the bio-film, or even lower levels of oxygen directly above the bio film.

I also noticed in the video earlier, even though the fish were directly on plants, it didn't look like there were a lot of them in the background. Again, just a hunch, but the range of colors this species is reportedly capable of changing from, light brown to green, would seem to be a suitable adaptation to an area with a sandy bottom and sparse plants. In this environment, most of the bacteria would be deeper in the sand bed. Although there would be species still on the surface of the substrate, those would be more rheophilic species and any layers which died below the top layer of bacteria would no longer be attached and swept away in the heavy current.

I'm not saying I'm correct on this, but it seems this would be a good biotope to try. Just my advice based on other species this has worked for, but I would start with a freshly set up tank with a thin layer of sand and very strong current in order to maintain this environment. Plant sparsely in pots to allow the roots enough substrate to remain attached. Use a mature filter from another tank to start.

One think I've noticed in tanks I've done this with is diatom algae seems to predominate all the available substrates after only a couple weeks and may be the reason I've had success with it since tracks can easily be seen where the fish have been eating.

Again, this is just a few random thoughts, but is where I would start.

Larry

[lurch1000]

Very interesting thoughts there Larry.

I wasn;t planning on going mad on substrate, but enough so the current doesn't wear it through. I have a bare patch in my fry tank where even with gentle refilling by pouring water over the sponge filter to ensure minimal substrate disturbance has appeared.

So, from the comments about wiping walls to minimise BOD, I shall forget the 3D backing. It was a thought as I acquired it with a job lot of other stuff.

The filter would be filled with mature media from my other tank, so got that base covered. I;m looking forward to creating this biotope. Anyone got any ideas what the plant is in that video by the way? Might as well start by getting one of those I'm not keen on pots from an aesthetic point of view, but I'm more interested in the tank being right than pretty. I may look to tying the plants I have to pebbles as a weight. One of the plants going in the tank will be Hydrocotyle leucophala, I have far too much in the 4', and that was only from one pot. Pig to keep the roots in the sand though! I think planting-wise, I'll mainly aim for them covering the three sides, and leave the front open.

Had my test pot of water standing since yesterday of tap +50% RO, shall be taking key readings later on as a comparison to my normal tap water.

[lurch1000]

Not got my notes to hand, but thought I'd post some very basic and approximate stats from memory.

My tap water is TDS:95ppm, pH:7.5, KH:~1 and GH:2-3. Phosphate is heavy from the tap. 1l tap with 0.5l RO threw up approximately TDS:70, pH:7, KH:~0.75 GH:~1. I need to buy the API phosphate kit as my super-sensitive JBL one can't really cope with the dilutions, the colour is a bit wierd, whereas the API kit has a coarser scale. Conductivity, off teh top of my head was 0.2mS/cm for tap and 0.8mS/cm for RO. FWIW, the RO butt was new from the shop, and I don't know how well they rinsed it before filling it, but at this stage, approximations will do as I'm unsure how the tank decor will affect anything.

Anyway, back to the point of this post, my tap TDS is as near as dammit the same as the shop I bought the fish from, but the pH is higher. From previous comments and other reading, the lower the TDS, the more the pH goes out the windows (so to speak).

I'd appreciate any info on which way to take this for receiving sensitive fish that have managed at least two weeks in 90TDS water with a pH of 6.8. Do I want to match TDS and pH, do I want to match just TDS? My tank pH was about 6.7 with little hardness when I received them, but the TDS was through the roof, hence the omso-reg shock conclusion to the investigations.

Loose plan (as the above may seem a bit pointless without "the plan") is to receive the A.dichromum in to similar water to which they have been kept, also receive some C.adolfoi (6) to the same water, and slowly adjust the water to more acidic and low TDS conditions as per the Upper Oricoco and Casiquiare conditions where they are found. I have so many papers still to get through, but I think I have a loose measure of where I want to be.

If anyone has any comments or suggestions with regard to pH and TDS matching, I'd be truly truly grateful.

Many thanks!

[MatsP]

I wouldn't worry about pH, and if your TDS is +/- 10ppm of what the shop's water is, I'd just drop them straight in [assuming the TDS hasn't changed much while the fish are in the bag, which of course is entirely possible].

Slightly confused that your EC is 0.8mS/cm on the RO water - are you sure it's not 0.08? I'd expect it to be lower than the tap-water, or something is very wrong somewhere, as your mix of RO and tap water is lower TDS than the tap-water TDS. Since the TDS meter is doing exactly the same type of measurement, the EC and TDS should follow each other [The same principle of measurement at least, measuring electrical conductivity, I'm sure it's possible to design a meter in more than one specific way, such as the frequency it alternates the current, and such things, and get minor variations due to those changes]

--
Mats

[lurch1000]

That would be something, dilute the RO then get water witha higher EC!

Mistype there, the 1l tap + 0.5l RO actually has an EC of 0.18mS/cm, doesn't quite line up with the TDS drop still.

Thank you again sir!

[dw1305]

Hi all,

quote]My tanks generally average a DO of 7.0 at 83 F. However, it takes some very specific work to do this, and I think the reason I do that work may be indirectly related to the problem here since it would be very difficult (if not impossible) in a heavily planted tank.

Not necessarily, planted tanks will normally have higher levels of aeration than non planted ones. This is often true even at night when plants are respiring and not photosynthesising.

There are 2 major reasons for this, one is that plants are removing ammonia from the water, and biological filtration is an oxygen intensive process, and any NH3 or NO2 that the plants remove doesn't enter biological filtration. The second is that during, and at the end of, the photo-period the tank water should be near saturation point with dissolved oxygen. Plants are evolving 100% oxygen in very fine bubbles (when "pearling" at 100% saturation) or the oxygen is dissolving before it ever becomes apparent as bubbles (at less than 100% saturation). If you compare that to an air stone, the air stone is producing bubbles which have a much larger volume to surface area ratio, and are only 20% oxygen.

You can think about retaining aeration as a 3 part process, one factor is ensuring as large a gas exchange surface as possible, this allows oxygen to diffuse in and CO2 out, and can be achieved by using a wet and dry trickle filter, having fast laminar flow in the tank or "increasing" the tank surface area with the turbulence from a venturi type outflow.

This last method leads us on to direct aeration from a air wall or air stone, again the smaller the bubble are the better, you could also have a spray bar that increases surface turbulence, either from beneath, or from above, as a rain-fall effect. In all these cases the actual diffusion of oxygen from the bubbles is minimal.

The 3rd method, as Larry suggests, is to reduce BOD, this is the total demand for oxygen of all the processes in the tank. I use the reduction of BOD (Biochemical Oxygen Demand) concept for tank water management as well, rather than saying something is "good" or "bad", you look at each item in terms of what nutrients it contains, how readily available they are, and how much effect it will have on BOD. A slice of sweet potato, or a prawn, will have much more potential to pollute than a much, much larger piece of wood, this is because they have readily available, soluble sugars and protein, that the wood doesn't, and therefore a higher BOD.

I've noticed in fry and "sensitive species" tanks it's very important to wipe down the walls and all ornaments/decorations/caves on a regular basis. I do this in order to limit BOD in the tanks. However, in the case of sensitive adults which are notoriously difficult to maintain this shouldn't be as important as long as good DO is maintained. That just doesn't seem to be the case though. I've theorized a range from a lack of proper food due to bacterial competition for substrate to grow through a direct sensitivity to the bio-film, or even lower levels of oxygen directly above the bio film.

Definitely something in this, a lot of successful plec breeders are OCD about cleanliness, against that a lot of fish keepers like a development of biofilm for small and difficult fry (I'm one of them). My suspicion is that either method can work, as long as you understand what you are doing and why. Items like mulm, dead leaves and wood don't actually add much BOD, as they have very little in the way of sugars or proteins that can act as bacterial substrate. The actual aufwuchs or biofilm itself is a matrix of algal threads with diatoms, rotifers, cyanobacteria etc and is probably largely neutral in terms of water quality, but may act as important browsing surfaces.

I also noticed in the video earlier, even though the fish were directly on plants, it didn't look like there were a lot of them in the background. Again, just a hunch, but the range of colors this species is reportedly capable of changing from, light brown to green, would seem to be a suitable adaptation to an area with a sandy bottom and sparse plants.

This is what Jools posted earlier in the thread

Species where collected in portions of streams with slow to somewhat moderate current. Water clarity was usually greater than 2m. Water temperatures ranged from 25 to 29°C and pH from 4.5 to 5.5. A. dichromum was typically associated with aquatic or semi-aquatic vegetation usually in streams or along the edges of larger streams

True aquatic plants are likely to be limited in their natural habitat, mainly due to low nutrient levels, and a lot of the substrate will be sand, but in the video the fish looks very much at home on the leaf (possibly an Echinodorus sp.?), and you can also see some biofilm development on the leaf as well, so it is definitely a true aquatic plant, or one that is adapted to submersion during extended periods of high water. Having seem the video I'd definitely have some broad leaved plants, Echindorus, Cryptocoryne or Aponogeton spp. would seem suitable (although the latter 2 are exclusively old world genera).

I wasn;t planning on going mad on substrate, but enough so the current doesn't wear it through. I have a bare patch in my fry tank where even with gentle refilling by pouring water over the sponge filter to ensure minimal substrate disturbance has appeared.

If you mix sand and coarse sand/fine gravel together the current will sort it. I usually do this in high flow tanks, and any bare areas (highest flow) I just locate some rounded cobbles.
You don't need a very thick layer of sand for plants to root in.

I wouldn't worry about pH, and if your TDS is +/- 10ppm of what the shop's water is, I'd just drop them straight in.

&

If anyone has any comments or suggestions with regard to pH and TDS matching

I agree with Mats. I'd then try and keep TDS pretty low by and ignore pH. You can feed your plants using the "Duckweed Index" approach <http://www.planetcatfish.com/forum/view ... weed+index>, but they will never grow lush and green like they would with EI and CO2, you are using the plants to improve water quality, and just feeding them enough to keep them ticking over.

Phosphate is heavy from the tap. 1l tap with 0.5l RO threw up approximately TDS:70, pH:7, KH:~0.75 GH:~1. I need to buy the API phosphate kit as my super-sensitive JBL one can't really cope with the dilutions, the colour is a bit wierd, whereas the API kit has a coarser scale.

All UK tap water is treated with orthophosphate (PO4---) to help minimise levels of heavy metals, it is called PIMS "phosphate induced metals stabilisation". It is quite tricky to measure phosphate, but I'd just ignore it. You could use a phosphate removing resin (something like "Ultiphos"), but plants are a better long term option for removal.

Sorry it is such a long post.

cheers Darrel

[lurch1000]

No need to apologise for a long post when it's that informative as yours always are.

Just a note WRT orthophosphate, it was my understanding from a planting freak that orthophosphates were not favoured by plants by other phosphates (mono?) were. May have that the wrong way round as I've slept since.

I shall monitor TDS/EC anyway as a guide for this tank. My tap water had somewhere just below 5ppm nitrate in it, I appreciate we take this reading with a pinch of salt (so to speak), but as I have dry salts and a stock solution of nitrate, I should be able to target and control any fertilisers if needed quite well.

[dw1305]

Hi all,

Just a note WRT orthophosphate, it was my understanding from a planting freak that orthophosphates were not favoured by plants by other phosphates (mono?) were. May have that the wrong way round as I've slept since.

It all starts as PO4---, then it is down to pH, in weakly alkaline water the hydrogen phosphate ion (HPO2−4) is the prevalent ion and in weakly acid conditions, it is the dihydrogen phosphate ion (H2PO−4). The main problem with all phosphate ions is keeping them in solution, the monvalent alkaline metal phosphates (sodium etc) are water soluble, most other phosphates are only slightly soluble or are insoluble in water. The hydrogen and dihydrogen phosphates are slightly more soluble than the corresponding phosphates, and they are all more soluble at lower pH values (below pH7), which is why the water companies add NaOH as well as phosphates.

cheers Darrel

[lurch1000]

Didn't managed to get the tank last weekend as the transport agent wasn't as available as first thought. However, I'm off to Cheshire tomorrow anyway, and will be picking it up and combining it with a bit of a business trip.

On to the reason I came here to post.... Been a tinkering a bit with some water, here are some results, and corrections to the previous ones now I have my notes to hand.

My tap water, as tested after 24h of standing at room temperature.
pH: 7.6, EC: 0.2mS/cm, TDS: 95ppm, KH: 0.75dKH, GH*: 2-3dKH, NO3: 2.5ppm PO4: high**

My tap water with added 50% RO water (again stood for 24h).
pH: 7.1, EC: 0.18mS/cm, TDS: 71ppm, KH: 0.3dKH, GH*: 1?dKH, NO3: >0 PO4: high**

As above, but with a small piece of oak bark added. The oak bark was first placed in a cup of boiling water and left to stand for 30 minutes as an attempt at a rinse. This mixture had been standing for 13 days after the above results before it got tested
pH: 6.5, EC: 0.15mS/cm, TDS: 64ppm, KH: <0.3dKH, GH*: X, NO3: X PO4: X

* GH tests, I have the JBL one, I've never got the hand of when it's turned, happily take a reccomendation on a "better" test. The last test was abandoned due to the staining of the water. Suffice to say, I can't see the GH having increased.

** Tap phosphates are high here (Yorkshire Water), I only have the JBL phosphate kit that reads to 1.8ppm, if I start doing crazy dilutions, I struggle to get a decent colour comparison as the shades are wrong, but it looks like it's over 10. One test I got on the diluted tap water was 18ppm, but who knows!

So, from this, my untouched tap water has a TDS of very close to the water the Acestridium will be previously kept in, pH as previously mentioned is higher, my hardness is lower. a hardness value of 6 was quoted, even if you add up all my hardness values it struggles to reach 6!

Speaking to a friend of mine off PCF about pH values for fish, he is of the understanding that the pH can affect the oxygen transport across the gill membranes, but at a low TDS with a small fraction of carbonate, pH would also be at the mercy of the CO2 equilibrium. So while I'm happy with the suggestion that pH is less relevant at low TDS, I'd be happier with a pH closer to the last water they were in!!

Any thoughts appreciated as always.

[dw1305]

Hi all,

pH would also be at the mercy of the CO2 equilibrium. So while I'm happy with the suggestion that pH is less relevant at low TDS, I'd be happier with a pH closer to the last water they were in!!

Changing pH by altering the CO3~HCO3~CO3 equilibrium occurs without changing the alkalinity, this is why planted tank enthusiasts use a drop checker and pH indicator to estimate their CO2 levels. In soft water pH isn't a very useful measurement and can vary from pH4 to pH8 during a photo-cycle as photosynthesis consumes CO2 and saturates the water with O-H.

You can't have stable pH in soft water without adding a buffer (like a phosphate buffer) which is self defeating, just don't get too hung up on the "perfect pH value". Just keep the TDS low and the water quality high, you've got plants that will help with water quality.

cheers Darrel

[lurch1000]

As ever, a brilliant answer!

Thank you sir!

[lurch1000]

I am a self confessed Google-tard, but I;ve finally managed to stumble in some info that doesn't cost me $40 each time I want one snippet of information.

So, some info on the Negro River's basic stats: acidic (pH 4.5 ± 0.9), low conductivity (17.0 ± 15.2 microS/cm) and solute-poor (TDS= 7.1 ± 6.7). (Source)

Found some other info on the pH distribution of the area, and largely ranges from very acidic to pretty acidic on the whole, not been able to find any conductivity reading that I can translate to microS/cm though, just a case of searching for the conversion, but I'm probably correct in assuming it's going to be half of nothing.

So, I'm thinking that while disregarding pH and concentrating on low EC/TDS is a way forwards, maybe a bit more of a nod to pH should be considered at this stage until it is known what these fish actually need.

My pot has stabilised at 0.13mS/cm (TDS 68), pH 6.4 and KH~0.3dKH. I'm now beginning to wonder if building the water from RO+sphag/bark/peat is going to be better than my current (cheapskate) approach.

[Mod edit: Fix Link so that it's clickable, as the default parsing cut it short]

[lurch1000]

When did the cat-elog get an update on these?! Stunning pics!

[Jools]

When did the cat-elog get an update on these?! Stunning pics!

I bought some...

Jools

[lurch1000]

Good man!

When?! How they doing?

[lurch1000]

Would you mind sharing water parameters?

[Jools]

They're in pH6.6 (tested before they went in) and a temp of 78F. I acclimatized them for a day in a slow drip + airstone tub. I've done one 30% water change with aged tap water. I've still got six, but I do not see them eat. They're in an established tank with Spinipterus (one species is daylight active, one is not) 30x15x12 with ambient light, anubias, wood and fine gravel. There is a fluval 3 (yes, it's a strong current) providing filtration.

I had a good look at the teeth of these guys and they are raspers not pads like many other hypoptopomines. Lord only knows what they do with them.

Jools

[lurch1000]

I believe your tap water is very soft with a fairly low TDS?

Interesting to see how they do, they look stunning, how long had you had them before the pics, and how long in total now?

Wonder if they're used on thin-leaved plants, or to scratch a layer off? Find out if you have holey Anubias

[lurch1000]

Very rude of me - thank you Jools!

[Jools]

Very rude of me - thank you Jools!

Not at all, wasn't expecting thanks... Anyway, yes, tap water is soft. There is alkaline rock in most of my tanks (or shells) just to keep things from getting extreme.

I've not measured the TDS on the tank water.

Jools

[lurch1000]

It's baffling as to what makes these tick. I know of some that perished in similar water, pH was a tad higher than yours, soft and low TDS etc.

We can reasonably put the demise of mine down to the ridiculous TDS the tank had got to, others, no idea, maybe the trauma of import. Do you mind saying where yours came from an when?

[Jools]

I wasn't going to mention it, but I bought mine from Rare Aquatics, I think the tank they were in looked a bit troubled (water a cloudy which is unusual). There was a lot going on so I didn't get time to ask Jo/Nick what was the issue. When I got them home I took 24 hours to acclimatize them. I don't normally bother with TDS for introducing fish from a known source and so didn't measure either the source or destination water.

The fish are still all there, but I've no idea what they are eating (if they are). Prepared foods are not taken as far as I can tell. Without a camera they're too small to tell if they're hollow bellied or not but they don't appear so. I get the feeling they're working the glass clear of mulm but as with many fishes likes this, I'll just play it by ear and write up a CotM at some point.

As to the silver bullet, I think DO is the key and, perhaps, keeping them in a established (read dirty) planted tank with decent water quality and current.

Jools

[lurch1000]

Thank you for the info Jools. Seems odd how one batch would take prepared foods and others wouldn't.

I know mine came via Germany, later ones I think came from SA. Wonder if anything can be read in to that.

[Jools]

I know mine came via Germany, later ones I think came from SA. Wonder if anything can be read in to that.

Only that the German ones would be a better bet as already acclimatized and transport losses already taken out. I missed which ones were feeding and which ones were not? What were they eating?

Cheers,

Jools

[lurch1000]

Mine were part of a batch of 6 via Germany and had been eating at least courgette.

On a courgette note, I stumbled across some comments recently by someone who had over blanched his, and it had gone soft which suddenly made it more palatable to more fish and invertebrates. Apparently it became a feeding frenzy. Not sure that's ovely relevant, but thought I'd share.

[Jools]

I tried cucumber but didn't note any munching going on. Were they eating the white or the green skin of the courgette? They're teeth bother me, they don't look like those of your typical hypoptopomine.

Cheers,

Jools