S. Nigriventris thriving, S. Petricola dwarf fading

mpw · Post by **mpw** » 12 Jun 2005, 08:09

My first post here although I've been a visitor for quite a while.

I have had 6 S. nigriventris and 6 S. petricola dwarf (dwarves?) for about 6 months in an 85 liter tank with a sand substrate, wood, plants, subdued lighting and many shady spots, together with 4 clown loaches and a few Otos. Water is very soft, pH around 6.8-7, temp 25. Feeding a variety of sinking spirulina and shrimp tablets plus mixed granules with occasional frozen brine shrimp, fresh cucumber and finely-chopped earthworms.

The S. nigriventris have tripled in size to about 10 cm and look great with spectacular dorsal fins. They are shy but become active if I sit quietly in front of the tank for a few minutes. The clown loaches and the Otos apprear to be doing fine, too.

The S. petricola dwarf are lovely fish, languidly cruising the tank like small sharks. However, they are still the same 5-7 cm size as they were when I bought them and quite thin. They now appear tiny in comparison to the relatively bulky S. Nigriventris. Two have died in the last month for unknown reasons and two of the remaining four seem listless, although their outward appearance seems OK, with clear colors and erect fins. I know these fish were born in a tank with relatively hard water so they have had to adjust to our softer water, although I've read on this web site that this should not be a problem. It's possible they are being outcompeted for food but I have occasionally added extra - both dry and frozen - and then watched them cruise by without much interest. I suspect I will gradually lose the remaining four unless I can change something.

Would appreciate any suggestions.

Post by **Silurus** » 12 Jun 2005, 11:24

I suspect that your problem stems from the water, despite the information available here.
Your petris seem to be displaying the symptoms of a fish living in water conditions too far removed from what it is naturally found in.
It might also be a temperature thing. What's yours?

mpw · Post by **mpw** » 12 Jun 2005, 13:06

Temp is about 25.

sidguppy · Post by **sidguppy** » 12 Jun 2005, 15:01

The tanbk is very small for such a crowd; I think foodcompetition is a big player here too, and all the substances given off by all the fish might curb growth as well.

I think it might be best to ditch the petricola's; these two species both live on "the opposite end" of the waterparameter-spectrum (what's in a word

), and it's highly unlikely you can ever fix the water to have both species very happy. always one will be thriving and the other one "getting by" at the most, if you catch my drift.

buying a second tank is ofcourse another option

bunjiweb · Post by **bunjiweb** » 13 Jun 2005, 00:25

I have 4 dwarf petricola and a "True" petricola along with 2 syno nigrita in a 50G tank. The water is not adjusted much at all. pH is about 7.8-8.0...Temp about 25-26.

I feed mine just on sinking tablets, they seem to thoroughly enjoy them, never had a problem feeding them. Try changing the brand of sinking wafers you use, i use Hikari all the way and the fish seem to love it.

Ben

sidguppy · Post by **sidguppy** » 13 Jun 2005, 17:49

nigrita and nigriventris differ a lot; nigriventris won't last long when kept at such a pH at all.....

nigrita even do fine when kept in a Rifttank, as a substitute for the more expensive multipuncs and petricola's.
like robbianus, ocellifer, eupterus and angelicus, this is a tough fish that easily adapts to different food, different water and even cichlid-company.

nigriventris is more like contractus (although not as fragile as those); suited for the well-planted softwater tank with bogwood and easygoing tankmates.

mpw · Post by **mpw** » 13 Jun 2005, 19:24

I think it is probably time to try a separate tank for the S. Petricolas and to boost the pH, KH and GH artificially.

However, I have read in quite a few places that S. Petricola is adaptable to different conditions so this is a little frustrating. For example,
http://www.planetcatfish.com/cotm/2001_06.php
See under Habitat and also Husbandry

SidGuppy, you surely have much more experience than I do, but if you saw my 85 litre tank I would be surprised if you thought it was crowded.

I don't plan on starting an ambitious Malawi tank but I would welcome any suggestions for some mild mannered, small and ideally colorful schooling fish from the Lake that would make good tankmates for the S. Petricolas in a tank with harder water and a higher pH.

Thanks everyone for the various inputs. This is an excellent forum.

Post by **Birger** » 14 Jun 2005, 03:38

The S. nigriventris have tripled in size to about 10 cm and look great with spectacular dorsal fins.

It seems like you are describing fast growing eupterus,maybe doublecheck and make sure you really have nigriventris

don't plan on starting an ambitious Malawi tank

There are many interesting small suitable fish from "Lake Tanganyika" shelldwellers,cyprichromis,Tang.killies

Good luck
Birger

mpw · Post by **mpw** » 14 Jun 2005, 06:13

I meant Tanganyika. Really!

Re. the species ID, mine look very much like this and spend a lot of time upside down.
http://www.aquahobby.com/gallery/e_Syno ... entris.php

Post by **Silurus** » 14 Jun 2005, 07:49

Then you have S. eupterus, not S. nigriventris.

mpw · Post by **mpw** » 14 Jun 2005, 09:16

Could you elaborate on why you ID it as S. eupterus?

Do you mean the photo on aquahobby.com is mislabelled, or are you basing this on the size info, growth spurt, or something else.....?

I've looked at the photos on plantetcatfish.com and elsewhere of both S. eupterus and S. nigriventris, and to my inexperienced eye there seems to be as much variation in appearance within the species as there is between them, although if mine get much larger I guess it will be obvious they are S. eupterus.

Thanks.

MatsP · Post by **MatsP** » 14 Jun 2005, 09:49

You can have a look in the Cat-eLog here on Planet Catfish, and compare the two. It's quite clear to me that the S. Nigriventis doesn't have the same spottyness as the S. Eupterus.

Check out these two:

In general, the Cat-eLog here is very good, thanks to a large bunch of scientists and amateur experts that correct any mistakes by someone else. This is not always the case for books or other web-sites. Often, people will put a picture up with the information they were given by the LFS. Since your local fish shop can't be experts on every one of the tens of thousand different fish that exist in the world, so they are likely to make a mistake sometime and again. As are the importers/exporters (in error most of the time, but sometimes they are "improving" what they've got).

I hope this helps.

--
Mats

Post by **Silurus** » 14 Jun 2005, 11:43

Do you mean the photo on aquahobby.com is mislabelled

That is precisely the case.

Easiest way to tell the two: look at the dorsal fins. Synodontis eupterus has a much taller dorsal fin. Also, young S. eupterus have a reticulate pattern that S. nigriventris does not.

Post by **Birger** » 15 Jun 2005, 05:47

Getting back to your original post the 85 liter tank will be to small for the 6 eupterus as you have probably figured out by now and they are probably outcompeting the petricola for food as well as the differences in preferred water conditions, and while you are rethinking your tanks occupants have a look at the adult size of clown loaches, they are an interesting fish but they get quite large as well.

check out
http://www.loaches.com/species_pages/bo ... nthus.html

Birger

mpw · Post by **mpw** » 15 Jun 2005, 05:53

Agreed. I now plan to sell the S. eupterus and will relocate the clown loaches to one of my larger tanks when needed.