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Q I've recently started a 2 foot South American Biotope with Cockatoo Dwarf Cichlids and Ember and Flame Tetras. the Embers came from a small species tank, but seem to have settle well in the 2 ft tank. I'm now trying to find some Corries that will live happily in 7.4 Ph and won't grow too big for the tank. I've got Corydoras melini who are enormous now and far too big for the new tank, also I have some Aspidoras pauciradiatus in a 35 litre but these seem too small to put in the 2ft. I don't mind what Corries I have, but want them to be happy with the Ph, I had a run a while back when I lost Corydoras Metae, Panda, Duplicareus, and Corydoras julii & trilineatus before I realised it could be the Ph that wasn't what it should be, so I haven't really bothered with them since. But somehow, no community tank seems complete without Corries



A I agree that your Aspidoras pauciradiatus would be too small for your tank and are better suited to a species tank. I would go with your normal bronze Cory's Corydoras aeneus, either the normal or the albino variety. I know it doesn't sound very exciting but you would have a better chance with the farm bred Cory's. I think your p.H. of 7.4 is on the border line for keeping Cory's but some of my tanks which I tested at the weekend are at 7.2 after introducing a different type substrate and they are doing fine. Some of my other tanks with silver sand are at a p.H. of 6 and they are thriving also so there is a wide p.h. parameter there. I don't know your tank maintenance routine but may be more regular water changes would help in the future. (Allan James)

A Perhaps try some of the smaller species such as habrosus. If your apistos are okay then corys should be too. (Graham Ramsay)

Q I have about 10 albino corys that are about a year old that I raised. I used sand in the small tank when they were little, and am using "small, red flint gravel" in the 55 gallon tank where they have been for about 9 months. The gravel is just about the size that it can be picked up with an airstone - sized hose and occasionally will lodge in that size hose. I also have a bunch of apistos in the tank, and a few rams. I just noticed this evening that about half of the Corys have no barbels (bummer). I had never noticed it until now (and feel like a poor custodian of the fish). The red flint gravel does have points opposed to being round, but I never anticipated it would damage them. I have 6 adult (3-4") Corys (breeders) in another tank with the same substrate and none of them have this problem. I have read that pointed substrate will cause them to damage their barbels, but didn't see this coming. I have also heard it can be a biological problem, but don't know any details.

I like the small gravel, as it cleans nicely and doesn't show all the dirt like a white-type sand.

1. Would I be better off with playground sand?
2. I have heard that pool filter sand is good to use because it is cured and thus no impact on ph, however I don't really like white sand.
3. Could this be a biological issue, and if so what is it? I have heard that ammonia can be a problem, but I think the apistos would have had problems before the Corys, and I don't think there was an ammonia problem. The apistos (cacatoides) were reproducing in the tank.
4. I was going to raise these for breeders. Should I give them away and start over(as I understand they use their barbels in the mating process)? I have about 25 in another tank that are about 3/4" long now.

I have tried to read some of the articles on this, but the info seems all over the map. I don't want to go to bare-bottom tanks, except for maybe when the Corys are small.

Since I am in the USA, I don't know that what is available to me would be consistent with other countries. I appreciate any references, explanations, and advice, especially what to use that is cheap and available in the USA. I have some concern the play sand is harder to clean than gravel.

Q Playground sand it is. I have heard that you are supposed to boil it and cool it down before using it. How important do you think that really is? I would like to see if the barbels grow back, and with sand that may be possible.





A I would go for playground sand. I have just added some of this to a small tank holding 6 C.habrosus and, depending on the maker of course, mine is not white, just a light brown colour, quite nice actually. As you say I don't think it is a ammonia problem but hard to say whether it is a bacterial problem, if you regularly clean the gravel out with your syphon hose you may be all right on that score so then it would point to the sharp edged gravel.Some Cory species are more prone to barbel loss than others. I do know that C.arcuatus are bad for this if you don't keep the substrate clean. Once you sort out your problem you can keep your Cory's, as 90% of the time the barbels will grow back, some better than others. I agree with you not to go with bare bottomed tanks as other recent posts have pointed out the pitfalls in this with scum forming on the tank bottom. (Allan James)

A If you just wash the sand in a bucket with warm or hot water and drain it off it should be all right to use right away. Another sand that I use is Silver Sand which here in the U.K. we get in the large builders Merchants. As the name applies this is a light coloured sand which is nice also, and safe. I used to in the past use bird sand which has bits of crushed coral in it and it helped to keep my p.H. up as I have very soft water. It wasn't the greatest looking sand as it was a dark brown colour but again safe to use after being washed. (Allan James)



















A I know that various similar corys will school together but I am wondering if there is any information, or if anyone has experience, to show what degree of similarity is required? I have a friend who has one lonely albino cory and I have 3 C habrosus that need a new home but I am a bit concerned that the difference in colour (more than the difference in size) will mean that they won't school together.






















A In essence Cory's don't really form a school as such but seem to "hang out together". It is true that most species that we house in our tanks go looking for food together but in other instances they also break away singularly, also I think the addition of your 3 habrosus to the one albino cory will be more of a plus point than the albino being on its own. They may not move around together but I am sure it will be more happier in Cory company.

A I've found that the grouping patterns change with numbers, Allan. One or two will behave (for them) unnaturally because there aren't enough bodies around. Get to four to six and they'll begin to relax. By the time you get to a dozen or more you'll see that there are sub-groups of similar numbers that the fish keep to within the overall group, individuals moving from one sub-group to another.As to similar colour patterns being morelikely to stick together, I'm not sure that's a fixed thing. My gossei and seussi groups never mixed to any extend but the nattereri and prionotos groups do but, similar to what I mentioned above, the two species associate but within that the species tend to keep to their own.It may be that fish with very different patterns don't associate because they live different lifestyles (if that isn't too anthropomorphic!) I have some C141 and rabauti in the same tank and you rarely see them together but, from observation, the spotted fish spend much more time in the open while the rabauti spend almost all their time in amongst the plants and bogwood. Something similar occurs with my arcuatus and melanotaenia. The former are always visible but the latter only appear if I disturb the tank. (Keith Jackson)

A I think it must be something to do with our own parameters, water, plants, how many in a group even light sources as my melanotaenia are always buzzing about at the front of the tank especially when I approach with food. Opposite on the other rack of tanks I have elegans, which I collected in Peru in 2000 that never appear apart from feeding time, and the tank next to this I have weitzmanni that are very shy and again next on I have panda that are always showing at the front and also bilineatus that are never shy since I moved them into my new Fishhouse, but previous to this in my old fishhouse, you couldn't see them. Strange (Allan James)


A Over the past week or so, one of my two Corydoras's has been acting sick: He swims as if drunk and settles down on the surface quickly or on the nearest plant. Today he seemed near death (i haven't checked my 20 gal tank in the last 1 hr). He appears pale. No growths are seen. I have had him for nearly 9 mos. His previous partner was found dead over 6 months ago and I bought another who seems to be OK. The other denizens appear OK, though one of my platy's had developed a swollen eye a week ago which has now cleared, and a few of the platys have died over the past several months (I am now on my third generation of these). Altogether I have 5 adult platys, about 8 or so juveniles with occasional fry added, an asian algae eater, 4 mollies and 8 neon tetras (the newest additions). The water is kept at 27 deg C (about 81 deg F) and the tank is heavily planted, with the plants supplying the oxygen. The CO-2, Ammonia, nitrites and nitrates all test "within normal limits". I have a bacterial powered filter system (Eheim Professional) which seems to be working fine. I feed the fish daily with granulated food, and must admit that I haven't been generous with the additional tablets meant for the bottom feeders. Could it be that the poor fish (who I've named "dopey" because from the start he would overlook the tablets when they were right by hm) has been malnourished and is dying of that?.  

A It's difficult enough identifying ailments in one's own tanks. Offering diagnosis and treatment advice on the internet is rarely productive. I can only repeat the advice I give to anybody with persistant problems which is to increase your water changes both in quantity and frequency. With your own specific setup I would say some of your fish have very different requirements in terms of water conditions. Also the Asian algae eater may be harassing your catfish. It's perhaps a little on the warm side too. (Graham Ramsay)

A I would agree with mummymonkey and as he says the temperature seems a little high for Corydoras. There are only a few that can stand the higher temperatures, Corydoras sterbai for instance but in the main they will do better at a mid 70sF regime and it is also very possible that he has caught something from the Platy's and has an internal bacterial problem. Corydoras are hardy fish but when something like this happens it can be very hard to halt the decline in the fish and I am afraid it doesn't look too good for him/her. (Allan James)





A Here's a thread going at another forum I belong to and one person is insisting they knew of a 6 inch long cory that attacked and killed small oscars. wacko.gif And they're warning others about keeping cories with neon tetras because the cory may "eat them." ohmy.gif

So is there any cory type cat that could possibly fit that description???











A Mmmm! sounds a bit odd to me. The only aggression you will maybe get with Cory's would be the bigger ones such as barbatus males who will spar with other males but aenus must be the most docile fish you can meet. The only aggression that I have ever witnessed, and this was about 20 years ago, was when I was breeding elegans and one of the males had small damage to the dorsal, again maybe males sparring for a partner. (Allan James)

A There is a story from years ago of someone diving in the Amazon basin and seeing a brochis species at 150mmSL, I think it was Heiko Bleher, but not sure. However Brochis are quite a peaceful species.Maybe a case of mis-identification and not a cory at all, just something similar. Certain large hoplos also can get a bit manic when feeding, but they are not known as being belligerent. The only other candidates I can think of, are young dorads. I used to look after a large Oxydoras niger, and it was housed in a tank with some pacu's, it wasn't aggressive towards them; but on occasion I observed it gently mouthing the pacu's flanks, the pacu's always swam off, but the niger never gave chase. (Adrian Taylor)


A Otocinclus: 1. I have two meds now that I haven't used yet. Methylene blue and Jungle Fungus Clear. I know MB can be used against ich, I've seen the JFC ingredient, nitrofurazone, listed in a few other brands of ich treatment. Which one would you pick?

2. I think I'll be dosing M1+M2 along side to prevent bacterial infection, or should I use the JFC for that? Edit: I just remembered I have Kanamycin soaked spirulina pellets I could feed him, maybe that's enough for bacterial prevention?

3. Obviously, I can't use salt, do any of these meds require smaller doses for scaleless fish? Any med combos here you would avoid?

4. I've read a bit about the ich life cycle, should I warm the tank and wait a day or two for treatment?









A It is a bit of a personal thing with me.. I just hate adding any medication to catfish tanks and if I do, I half the dosage for scaleless fish. What I would do myself is to higher the Temperature to about 86 to 88f for about five days and this should kill the life changes of Ich. Just keep an eye on your Otto's for signs of stress and also a good idea is to increase the aeration in the tank as the oxygen supplies can drop the higher the temperature is. (Allan James)

A I also raise the temp of the tank as soon as i see whitespot and increase the aeration in the tank, i find this tends to do the trick avoiding the use of meds, if done at the fist sign of an out break. (clunk)

A Hi! new here, but have had otos for a little while. When my guys got ich (Petco fish aren't the healthiest...) I did some research, as I knew that scaleless fish are more delicate when it comes to meds. During a search I found a site called monsterfishkeepers.com. As you can imagine, they are dedicated to monster sized fish - including catfish. smile.gif They absolutely raved about Ich Attack by Kordon. It's a natural remedy made from naphthoquinone. It doesn't mess up your bio filtration, and is very gentle on the cats while doing it's job on the ich. It does take a bit longer to get rid of all the ich - but the full life cycle is longer than what standard meds suggest medicating fish at anyway. My guys were clear of ich within about 5 days and I actually treated them for almost 3 weeks with no ill effects whatsoever! In fact they fattened up very nicely during that time. I also agree with raising the temp if you chose not to use this and even if you do! Getting the temp into the 80's for at least 5 days should do the trick too. (nj2tou)

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