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transporting Corys 6/28/16
albino Cory barbell loss, going for air 11/9/14
My name is Gabby and I'm new to aquariums (had one since August) and loving it.i've slowly built a community tank (doing lots of research) since then and it's gone quite well.
I have a question about my albino Cory. I have a group of four and yesterday saw that the smallest one had lost his barbels. Today, I've seen him go up for air quite a bit, much more than the others. He's still quite
active, but during feeding seems to have eaten less than the others. Should I just keep monitoring him? Any suggestions?
<Catfish lose their barbels for two reasons. Or rather, there are two things going on that interact, resulting in the barbels getting shorter.
Keeping Corydoras catfish in tanks with gravel (especially sharp gravel) rather than sand causes the barbels to get damaged. Very fine (sometimes called "pea") gravel is better than regular aquarium gravel, but the best
substrate is silica sand (a lime-free sand, sometimes called "pool filter" or "smooth silver" sand). What happens is the barbels get damaged, and that's when the second part of the process, bacterial infection, sets in.
The bacteria cause the tissue of the barbel to die back, and over time the barbels get shorter and shorter. Improving filtration and water flow along the bottom level of the tank can help. Some filters (especially small
internal canisters and hang-on-the-back designs) often don't "suck" much water from the bottom and the outflow is very much directed along the top of the tank. This means the lower half of the tank suffers from low oxygen
levels, which causes catfish and loaches to swim up and gulp air. Note that under optimal conditions Corydoras rarely gulp air -- they're very much "facultative air-breathers" meaning they only breathe air when forced to do
so. That's unlike Bettas which are "obligate air-breathers" meaning they will suffocate if they can't breathe air because their gills are proportionally smaller than they should be (in the wild, Bettas live in places where the water doesn't hold much oxygen, so relying on their gills alone would be pointless). Anyway, under better conditions the barbels grow back very quickly, and on healthy Corydoras you'd be surprised how long they get, not far off half an inch!>
I also have a question about his lost barbells. When I decided on Corys, I decided on sand. The guy at the aquarium shop told me coral sand works, but now I'm wondering if it's the cause of his barbell loss.
<Coral Sand was a terrible choice. Bad advice from the retailer there!
Coral Sand is made of limestone. It's from the sea, basically mashed up seashells and corals. It makes the water hard and alkaline (i.e., raises the amount of minerals in the water as well as raising the pH). Over time, this stresses most freshwater fish. (Not all: livebearers and Rift Valley cichlids LOVE coral sand because it creates conditions they want. But Amazonian and Southeast Asian fish come from soft, acidic habitats and they aren't going to do well in tanks with lime-rich sands.>
The other three and their barbels are fine. Is this sand too rough?
Any thoughts or recommendations would be much appreciated. This little school is rivaling my Betta for favourite status, and I want to make sure they are healthy and happy.
<For sure a fun group of fish, the genus Corydoras.>
Thanks in advance,
<Most welcome, Neale.>
Re: albino Cory barbel loss, going for air 11/9/14
Thank you for your quick response! I'll go out and look for silica sand right away.
<Cool. Aquarium shops sell it, but it's often cheaper at garden centres.
Just clean it well, or you'll make the tank really cloudy.>
What would you suggest to increase oxygen flow at the bottom of the tank? I have a hang off filter.
<If all else fails, an airstone weighted down so it draws water up from the bottom of the tank (that's what the air bubbles do) to the top of the tank.
Cheap and cheerful. Alternatively, there are all sorts of small pumps called powerheads that do the same thing electrically. Finally, you could buy a small internal canister filter and place it somewhere at the bottom of the tank, maybe hidden behind some rocks or plants, and let it push the water around.>
Man, so much to learn still!
<Part of the fun of the hobby is the learning. Corydoras are easy fish, and very reliable for beginners, but there are one two issues with them. Would direct you to this page:
Various links at the top that will take you to interesting/relevant articles. Cheers, Neale.>
Seeking info about Callichthys 12/14/08 Hi
there! I am back with yet another question, I hope it's not too
much trouble. The LFS in my area is going out of business,
unfortunately. They are sticking around for Christmas, and then they
are calling it quits. Naturally, I was in there shopping for deals...
In with their goldfish was what I initially thought was a porthole
catfish, but after Googling around believe to be Callichthys
callichthys. (It was simply labeled "armored catfish", which
could mean anything!) It looks similar to the fish in the link below:
It was a dull olive green/grey color, so possibly a female? I believe
this fish is also known by the common name Cascadura ("hard
shell" in Spanish). Does anyone know anything about this fish, or
know of a place to find more information? I can't seem to find much
about them in my books, and the online information I have found has
been spotty. Some websites say they get to 5" long while others
say 8" or even 10" - and the acceptable tank size starts as
low as 15 gallons, which I am certain can't be right. I have an
unoccupied 29 gallon tank that I was going to turn into a brackish tank
for guppies and platies, which might work out if this is indeed a
brackish tolerant species. (We're only talking about 1.003-1.005
SG.) I imagine this catfish would keep the fry in check, which is fine
by me! If I knew he would outgrow the tank, I could take my time
finding him a more spacious home. Does this sound like an ill advised
plan, or could it work? I never rescue fish from pet stores, because I
know this only encourages them to restock. However, since the store is
folding, I thought "just this once..." since I doubt anyone
around here will appreciate a catfish like this. Thanks so much for any
help! Happy holidays to you all, Nicole <Hi Nicole. The Porthole
Catfish is typically Dianema longibarbis, a smallish (10 cm), midwater
schooling catfish closely related to Corydoras. It's named after
the row of roundish black blobs along the midline of the body, like
portholes on a ship. It's a pretty good community tank catfish. Not
a brackish water species, but otherwise adaptable. Now, Callichthys
callichthys (the Cascarudo) is quite a different beast. It's quite
a bit bigger (up to 20 cm) and unlike Dianema doesn't really swim
about in midwater and prefers to slither about on the substrate between
making mad dashes to the surface to gulp air. It's body is largely
unmarked, but the pectoral fin spines have a distinctive orangey
colour. It has tiny eyes! Callichthys callichthys is incredibly tough,
and will tolerate slightly brackish conditions (around SG 1.003)
without much bother. Hoplosternum littorale is a bit more of a brackish
water specialist, and would be my recommendation for life with guppies
and mollies. But there's not much difference between the two fish
otherwise. Both species are boisterous, semi-aggressive at feeding
time, but otherwise good community fish. Cheers, Neale.>