Trying to breed Platydoras costatus

[Kati]

Hi everyone,

I'm looking for any information related to Platydoras costatus reproduction or natural habitats. Actually, since there's probably not much available, info about other doradids would also be much appreciated.

And yes, I know there are no reports of this fish spawning in captivity besides after hormone treatment. I think I may have a pair. Rumour is these fish have spawned spontaneously in their previous owner's tank, but I have not been able to contact him for making sure and asking for details.

The fish seem mature, and they hang together all the time. They even hide in the same cave during daytime. The female is a bit bigger and really plumpy compared to the male.

I'm currently keeping the fish in a 200-liter tank by themselves and trying to feed them well with frozen bloodworms, black mosquito larvae, a few kinds of tablets and self-made shrimp mix (shrimps, mussles, fish, veggies, vitamins... originally for my discus and other cichlids). Water's really soft, KH around 2-3°, pH around 7, 25°C. The tank is furnished with fine sand and bogwood.

I admit to having a lot of questions unanswered... What time of year do these fish spawn? Do they need a trigger? Rainy season simulation or steady environment? I read somewhere, Baensch Atlas I think, that some doradids build some kind of a nest out of plant parts and stuff. Do these? Where - in a hole, bush, surface..? Anyway, I think I need to add some building material to the tank just in case.

Any info or ideas would be very much appreciated!

Thanks,
Kati

[Marc van Arc]

Hi Kati,
No answers alas, but a question to you: Could you state that your male has a complete dark coloured belly and the female has lighter coloured irregular lines running over it?
Thanks for your reply.

[sidguppy]

Marc; that's Orinocodoras eigenmanni, with the squiggly lines....

Platydoras just have a white or black belly with no markings, except that the "color" looks a bit smudgy.

I admit to having a lot of questions unanswered... What time of year do these fish spawn? Do they need a trigger? Rainy season simulation or steady environment? I read somewhere, Baensch Atlas I think, that some doradids build some kind of a nest out of plant parts and stuff. Do these? Where - in a hole, bush, surface..? Anyway, I think I need to add some building material to the tank just in case.

Kati, that's a lot of questions!
time of the year: NOW! their spawning season is in the rainy season, and that's our fall/autumn/winter here.

All fish need triggers, but to try a few:
-temperature drops! (when it rains, cold rainwater falls in the warm rivers, so...). You can do this by adding water that's a bit colder. the best way to do this is by using a shower or a watering can with a showerhead! this way the water is "spread out" and you can safely drop 20'C water in a 25'C tank.....in other words: imitate the monsoon!
of course a period of prolonged heat before doing all this, can help, as it too imitates the change of climate.


-salinity drops! ditto; the addition of much rain will drop the hardiness for example. You can imitate this with collecting rainwater (doh), and mixing it with hot faucetwater to get a nice mix. do NOT replace all or most of the tankwater with rainwater! another trick is demineralised water or the use of certain equipment, but this doesn't come cheap. You can combine this trick with the one above, of course.

-foodexplosion. after months of fasting (this tells you much: you probably need to fast your fish a few weeks), suddenly there's rain and with it a bloom of plancton and of course a lot of fry too, to feed on. Another add-on is that the forests flood (the Amazon Rainforest is a floodplainforest), and the fish are now able to reach fruit on both the forestfloor as well on the trees (!), many Doradids are fruiteaters! You can safely try and feed your fish small bits of kiwi without the peel, tiny bits of apple (ditto), bits of mango, grapes, berries, and tropical fresh fruits. THE way is: go small.....tiny add-ons are much better (and safer!) than dropping half an orange in the tank

-nestbuilding is documented about Amblydoras hancocky. it is not known about any other Doradid, but it might be possible. If so, make sure to have leaves (well rinsed oak and beech are safe), moss, floating moss (riccia), Floaters (Limnobium, Pistia, Lemna, Salvinia etc), a few nice caves and a large piece of flat (to rest on!) rock or bogwood wich is about 10 cm below the surface. Bubblenestbuilding cats (Hoplosternum, Megalechis) like to "sit" real close to their nest. highbuilt nesting places are recommended.

hope this helps

[Marc van Arc]

True Sid, quite right.
Kati: same question slightly adjusted:
Has your male a black belly and your female an off-white one?

[Kati]

Ok, so it's the basic "Corydoras method" with some twists! The fruit thing is new. I have sometimes fed my fish with pieces of banana though...

As for the salinity drop... R/O is way bigger than my budget, and rainwater is hard to handle this time of year (put a bucket outside and with luck it'll get filled with rain but if you're not quick to collect it, the water may freeze anytime and break the bucket... ). I think I'll rely on the old peat method. The water here is pretty good as is, and a bit of peat makes it almost perfect.

-nestbuilding is documented about Amblydoras hancocky. it is not known about any other Doradid, but it might be possible. If so, make sure to have leaves (well rinsed oak and beech are safe), moss, floating moss (riccia), Floaters (Limnobium, Pistia, Lemna, Salvinia etc), a few nice caves and a large piece of flat (to rest on!) rock or bogwood wich is about 10 cm below the surface. Bubblenestbuilding cats (Hoplosternum, Megalechis) like to "sit" real close to their nest. highbuilt nesting places are recommended.

Ok, I'll see what I can do. The others are no problem, but tree leaves are hard to find this time of year. Maybe I can prune some of the worse leaves on my Echinodorus or Anubias to get some safe building blocks.

Thanks a lot, sidguppy! This helped a lot.

Has your male a black belly and your female an off-white one?

I'll get back to you on this after I've messed around in the tank and seen the fish.


Kati

[pturley]

We caught a pair of Platydoras costatus in a cool clear-water stream in Peru in January '98. They were way up under a deeply undercut bank in the root mass of the plants on the surface. The roots from the weeds/grasses were the only thing holding the bank of this stream together. They were the only two we caught on the week long trip, however at other times of the year they were suppose to be more common in white-water.
They caught in the same sweep of a 10" x 12" pond net. We actually laid down in the stream-bed and reached under the bank as far as our arms + the three foot long net could reach. The fish were small and I didn't conclusively ID them as a pair at the time. (Too bad though, eh? )

Here is a picture I took of them on the sand.


Perhaps the migratory pattern for these fish is simply that, from white to clear with the expected chemistry changes.

Based on what I have seen, perhaps nest building inside a cave? Good Luck.
Keep us posted of results.

[pturley]

Since my post an hour or so ago I keep thinking about this one...
Over the past several years, I have milled over various ideas to try to incorporate my field observations into an aquarium with these fish. I even actively worked with this species for over two years but had given the fish up a couple years ago.

What about a large slate or tile cave with plastic plants siliconed to the roof? Or a large flower pot with a hole chipped into it inverted with the same? The root mass under the bank had a similar texture to soft plastic plants. Also you could add unmilled sphagnum moss (long fibers) to the tank so they could add materials to the nest if needed, if this is truely what they do?

Kati,
I think I may have to join you in working with this species again! Time to start building!

So many catfish, so much to discover, so few tanks, so little time!!!

[Kati]

Just finished rearranging the tank. I piled some driftwood almost up to the surface so that there are caves below. I also added some vallisneria which leans over the driftwood pile like a roof, a few fistfuls of Cardamine lyrata which float just under the vallisneria and some Microsorum fern bushes here and there on the bottom around the pile.

What about a large slate or tile cave with plastic plants siliconed to the roof? Or a large flower pot with a hole chipped into it inverted with the same? The root mass under the bank had a similar texture to soft plastic plants. Also you could add unmilled sphagnum moss (long fibers) to the tank so they could add materials to the nest if needed, if this is truely what they do?

Ahh... I see more rearranging coming up...

There's plenty of room left in the tank. The driftwood pile and the surrounding bushes take only about one half of the tank (it has 100cm x 50cm bottom). I think I'll build something bank-like in the other end. I have some floating cork pieces somewhere that might become useful, but the flower pot doesn't sound bad either. Maybe I can find room for both and let the fish decide if they're useful or not.

I don't know if it's too late in the winter for this, but I also raised the temp a bit and decided to feed the fish less and change less water for a while, a few weeks maybe. Hope they don't have a calendar.

Thanks for your comments pturley! I'm getting wiser every hour . And good luck with your fish!

Has your male a black belly and your female an off-white one?

No. Both bellies are white. I'm getting more and more curious... why do you ask?


Kati

[Marc van Arc]

I was hoping you could affirm my belief that you could sex them on that feature.
But if you say you have actually have a pair and both bellies are coloured alike...
Can you shine a light on this issue, PTurley?

[pturley]

When I had a decent sized pair, I was relying more on overall body shape (like Corydoras) than differences in coloration. I didn't note any color differences, however that is no indication whether it was present or not.