Otocinclus Temperatures

[TP]

Whislt looking through Baensch to update temperature information in the cat-elog I have found the following differences in Otocinclus

O. macrospilus - Cat-elog = 21-26, Baensch = 24-28, FB = N/A
O. cocama - Cat-elog = 21-25, Baensch = 24-28, FB = N/A
O. affinis - Cat-elog = 20-26, Baensch = 18-22, FB = 20-26
O. vittatus - Cat-elog = 21-26, Baensch = 25-28, FB = 20-25

There are various things I could do, I could just merge the temperature ranges or just leave them as they are but I think they are different enough to debate the matter.

[Mike_Noren]

I'd say merge them. AFAIK all of them do just fine at any temperature between 20 and 30 celsius, and affinis (and probably vittatus, perhaps depending on where they were caught) can also handle considerably lower temperatures.

(O. affinis is a subtropical species from Argentina and in parts of its range there may even briefly form ice on the water, O. vittatus has an enormous range from the Amazon to Argentina, from tropical to subtropical, macrospilus is a tropical species, and cocama... well, I don't know where in Peru cocama lives, so I don't know what temperatures it normally sees but it's presumably tropical.)

[racoll]

I wouldn't trust the Baensch atlases!

Seidel and Evers' Wels Atlas I would be a much better text for this kind of info.

In agreement with Mike, I have kept several different

Otocinclus

(mixture of spp. from Peru and Colombia), and all did fine across a range of temps (22-28C).

[MatsP]

I find this quite often, and I have the same problem as you - "What do I do now?"

One thing I often consider is other fish from the same area - however, I'll also immediately also admit that this doesn't always work - for example, if a fish lives in a small river that flows at fast down off a high-level area, it will be different from a low-land river, flowing slowly. The slow-flowing river will pick up more ambient temperature.

I'd expect that Otocinclus spp. live in smallish waters, rather than the main rivers (or possibly the slow-moving edges of the main river). They certainly do not live in very deep water. This means that it's likely that they are NOT the same temperature as the main river channel.

Sorry, this discussion isn't actually telling you what to do - I'm just explaining the difficulty in coming up with "the right" answer.

Also, living in shallow water, is likely that they indeed tolerate quite a wide range of temperature - shallow water will vary in temperature more than deep water, depending on different weather conditions (e.g. rainfall will drop the temperature quite significantly, being hit by sunshine will raise it). This supports Mike's suggestion.

I also do agree with racoll: Wels/Catfish Atlas is a better reference.

Can I post now without another post coming ? ;)
--
Mats

[racoll]

Wels Atlas I has a accounts of the habitats of many of these species, including probably the most common one in the trade,

Otocinclus vittatus

from the Colombian Llanos.

Temperature data are also presented from the wild, and the book is well researched, so I can't see any reason for not using the same temps for the cat-elog pages.

[TP]

Thanks for the replies, so far merging seems the preferred option.

To clarify on the book I am using it is the Baensch/Mergus Catfish Atlas volume 1 by Evers and Seidel ISBN 3-88244-064-3. Is this the same as the Wels Atlas 1?

[MatsP]

Yes, that's what I mean by "Catfish/Wels Atlas" - "Wels Atlas" being the German verison, Catfish being the term used on the English Translation.

--
Mats

[racoll]

Yup, thats the one.

I thought you meant the one below TP.

As you probably know, wels (pronounced velse) is German for catfish. I still call them by the German name though, as its less confusing that way, I think, and volume two is still only available in the German edition anyway.

[TP]

Thanks Chaps, it all makes perfect sense now!

[MatsP]

TP (or anyone else [1]): If you fancy something to do (with regards to filling in temperatures), the link below gives you all fish that hasn't got any temperature listed:

List of "no temp" fishes

The link is dynamic, so you can bookmark it, and it will show you an accurate list of the current situation whenever you look at it.
Currently, it lists 1634 species, which means that roughly two in every three fishes in the Cat-eLog do not have any temperature listed with it... I try to look them up when I can, but it's hard work - and having a source.

I listed them in order of hits, so the "most important" ones are at the top of the list.

[1] If you don't have Cat-eLog editing access, you will need to arrange that with Jools first, of course...

--
Mats

[Bas Pels]

I'd say merge them. AFAIK all of them do just fine at any temperature between 20 and 30 celsius, and affinis (and probably vittatus, perhaps depending on where they were caught) can also handle considerably lower temperatures.

(O. affinis is a subtropical species from Argentina and in parts of its range there may even briefly form ice on the water, O. vittatus has an enormous range from the Amazon to Argentina, from tropical to subtropical, macrospilus is a tropical species, and cocama... well, I don't know where in Peru cocama lives, so I don't know what temperatures it normally sees but it's presumably tropical.)

Personally, I think if a species has a wide-temperature range, that does not nescessarily any individual is able to cope with that range - a tropical O vittatus is adapted to hot water, while a southern O vittatus can cope with other problems.

I think a tropical O vittatus, kept at 10 C, will face exactly the same problems as a O mactrospilus has - and both will, I think, die because of far too cold water.

Therefore, a temperature listing should, ideally, be either more specific - depending on the collecting locality an other listing, or just be restricted to what 90 % of the fish in trade - all coming from Colombia, thus tropical, face. With a note, obviously

The people who go to collect their own fish, will usually know more about local temperatures

[Mike_Noren]

Yeah, I wouldn't recommend exposing the northernmost populations of vittatus to the lowest winter temperatures experienced by the southernmost populations, even though gene flow means they MIGHT handle it, but I'd still bet good money that any temperature between 20 and 30 degrees is acceptable indefinitely for any species of Otocinclus, with the sweetspot roughly in the middle of that range. And that's pretty much what one'd get by merging.

I don't see any point in being much more specific than that, partly because it simply wont matter to the fish, and partly because my experience is that highly specific advice regarding parameters such as temperature and pH tend to stress inexperienced aquarists who think the ranges are absolute, with certain death waiting half a unit outside of it.

That said... It might be good if there were a reference for the temperature, and then one must pick one source. I would NOT recommend Baensch, as it is riddled with errors.

[Jools]

That said... It might be good if there were a reference for the temperature, and then one must pick one source. I would NOT recommend Baensch, as it is riddled with errors.

I recommended Baensch to Tony, working on the basis (as we are doing now) of getting data in and refining. I was unaware of a better single source for a range of catfishes - what source would you recommend Mike?

Jools

[MatsP]

Are we talking about Beansch catfish atlas or Baensch Aquarium Atlas. In my mind there's quite a bit of difference.

Any work that has hundreds or thousands of fish listed will have some errors.

--
Mats

[Jools]

We're talking about the fish Atlas, not the catfish one.

Jools