Have irreparably harmed my Cory? 3-5-09 Hi. I moved some slate from my 20 gallon to my 40 gallon tank last night. Later on, I noticed my 3 Peppered Corydoras were not moving and my smallest was laying on his side. My other 3 Albino Corydoras along with Platy and 2 fry seemed okay. Am and Nitrites 0. I did 40 percent water change prior to bed. Upon waking this morning, all Corydoras were listless and I thought the smallest one was dead at the top stuck in a floating plant. Am and nitrite still 0. I scooped him out and tossed a good foot into a bucket. He wasn't dead. I immediately tossed him back in the tank (so I thought). I went and prepared some water for another change, came back and found him on the side of the tank ( still breathing). I panicked and put him in a bucket with some tank water and a couple drops of Methylene blue and an airstone while I changed the water and added a Eheim liberty 200 filter to further help conditions in the main tank. All the other Corydoras have perked up. The other is back in the tank floating at the top on it's side, it did go back down to the bottom for a few minutes and now it's back up top, barely breathing. I don't want to make the mistake of considering it dead again, but I don't want it to suffer. Should I euthanize this fish? Wait a bit? I feel like I'm in a fish horror story and I'm the bad guy which I guess I am. :( Gina <Hi Gina. Adding Methylene Blue without good reason is never a good idea. If you see unhappy fish, it's almost always an environmental issue, possibly poisoning. The latter is often a problem if you've been doing painting or anything else that releases fumes into the air. Because Corydoras are air-breathers, they're particularly prone to this type of poisoning. Assuming water quality is good, I'd check the temperature, pH, hardness, and that water circulation is adequate (i.e., the filter isn't running slow), and that there's nothing rotting in the tank that could be using up oxygen. Change 50% of the water now, and 50% early the next morning. Essentially try and flush through lots of clean water. Have you added anything new? Plants? Fish? If so, consider Ick and Velvet as possible stowaways, and act accordingly. Corydoras are pretty robust, and I'd not count them out too soon, but do observe closely for the next few hours. A photo would help us identify problems. Cheers, Neale.>

Re: Have irreparably harmed my Cory? 3-5-09-09-09 Hi Neale. The only thing I did was caulk up some holes in my wall a few feet from the tank the Cory is in. I don't know if that factors in. <Hmm... certainly possible if any types of solvent were involved. By default, when doing home repairs nearby your fish, keep windows wide open and a good strong flow of air through the room. Obviously moving the fish to another room is even better, but not always possible.> I've attached a picture, he seems worse today (not attempting to move away). I've done the water changes as instructed and all other fish in that tank seem okay. I did add some rock to the Cory's tank that I had bought for a redo on my 10 gallon tank that was left over. <What kind of rock? Some rocks are safe in fish tanks, but many aren't.> It was in the 10 gallon for a few hours before I moved it. <OK.> I mention the 10 gallon (in a different room) because I woke to find my six new Kuhli Loaches (had about 3 days) were all dead. <Suspect these were in bad shape before purchase: they are VERY underweight. If you look at them, their heads are bigger and thicker than their bodies. Since the skull doesn't shrink with starvation, but the muscles around the body do, this is usually a sign the fish is starving. In fact a healthy Kuhli will have a chunky body and usually a distinct "shoulder" behind the head where its body is obviously more robust that the head. So in this case, you may have come home with weak fish, making things difficult.> I had recently redid the tank for them (rocks, sand). I added a Eheim Aquaball and kept the sponge filter in the tank. When I came home from work last night, one was floating at the top in a plant (usually stays on bottom during day) but eventually moved down. I thought it was because I had put my Betta in with them and he bullied him. So I removed the Betta. <Bettas and Kuhlis normally get along fine.> Then at bedtime, turned off the lights, threw in an algae wafer (new bag bought last night) and checked on them before bed and they were swimming and doing figure eights, very active. Then all dead this morning. Am 0 Nitrites 0 Nitrates 20 PH 6. I've been struggling with low PH and had removed all driftwood from my tanks and all have had several water changes, the PH doesn't seem to be moving. <A sudden pH change certainly can kill fish. Is the pH 6 all the time? Or does it go up and down? If you have a pH of 6, it's likely you have soft water. I'd recommend fixing that by raising the carbonate hardness. Various ways to do that: commercial pH buffers (7.0 would be ideal); adding a small amount of crushed coral to the filter; or adding a 1/4th to 1/2 dose of Rift Valley cichlid salt mix (not normal salt!) to each bucket of water. Do see here: http://www.wetwebmedia.com/FWsubwebindex/fwsoftness.htm Oh, and do make sure you aren't using water from a domestic water softener; that's very bad for fish. Only use drinking-quality water.> I just bought and set up the 40 gallon tank ( I don't know if you remember our conversation last week ) and now I'm thinking of chucking it all except the Betta and a 5 gallon. I don't understand what happened the last couple of days at all and don't want to do anything until I do. <I'm not 100% clear what's going on, though I suspect the sick Corydoras and the dead Kuhli loaches are separate issues. Now, do remember that the bigger the tank, the more stable it will be, so keeping a 40 gallon tank will be miles easier than a 5 gallon, all else being equal. So don't get too disheartened! But please, go slowly, and do feel free to ask as many questions as you want. I think once you understand the issues behind soft water and pH changes, you'll be able to see the dangers you need to avoid. Cheers, Neale.> Re: Have irreparably harmed my Cory? (RMF, would appreciate input)<<Ok>> 3/9/09 Hi Neale. Thanks for all your help. <Most welcome.> The pH in my 20 gallon tank that has been running for 2.5 months is at 6. I added Seachem's Neutral Regulator with a 25 % water change Sat night and again Sun Morning. It doesn't seem to budge the pH. <Hmm... this is a very low pH for a community tank. While not in itself a disaster provided you stick with soft water fish only, it would be the wrong place to keep hard water fish like livebearers. My gut feeling would be that if you can't beat 'em, join 'em. Choose only fish that will enjoy these conditions.> I'm reluctant to add it directly to the tank as I wanted to raise the pH slowly. <Correct. You should never add these chemicals directly to the tank. Instead, add them to buckets of water. Alter the water in the bucket, and then use it to replace a bucket of old water in the tank. Over the weeks, the aquarium will gradually shift from whatever the conditions are in the aquarium to the conditions you are creating in each bucket of new water.> With the water changes, the pH will move up towards 6.4, but within a few hours drops back to 6 (the lowest my test goes). <Implies a variety of things, though most likely a combination of high stocking (lowers pH via organic acids, nitrate, etc) and lack of carbonate hardness in the water (nothing to inhibit pH decline). Certain materials, notably bogwood, will also lower pH.> I get the same readings and results in the 5 gallon tank that has the Betta. <OK, does sound as if you have very soft water. This is tap water, right? Not from a domestic water softener? You should never use water from the latter.> I purchased one of those test strips for alkalinity. <OK.> Currently in the 20 gallon (which houses 3 Platies, 1 fry, 6 Corydoras (the sick one is swimming around and looking for food a bit now) : pH 6 Hardness 120 (which reads as moderate not soft? Also, I do have build-up around my faucets) <<This could be salts, not of Ca, Mg... not contributing to hardness... RMF>> Alkalinity 0 Nitrite and Nitrate 0 Ammonia 0 My tap water comes out (tested from inside and outside sources, tested immediately after drawn and then after aerated for 24 hours) pH 8 Hardness 120 Alkalinity 120 (sometimes looks more like 180) Ammonia 2 + <<?!. RMF>> Currently in the 40 gallon which was filled with conditioned water, pH 8, 4-5 days ago and has been running with Eheim filtration with temperature set at 80 degrees. The Alkalinity in the 4 days has dropped from 120 (180?) to 80. pH from 8 to 7.6. I added a full dose of Seachem's Regulator on Saturday to this tank. <I'm getting a déjàvu feeling here! For one thing, you're using strips, and these seem to be less reliable than liquid test kits, so if possible have your local aquarium shop test some water and compare it to the results you get. But secondly, there seems to be a thing with the water supplied to some (American?) households where the water chemistry rapidly changes of its own volition within a few days. For whatever reason, it isn't something I've come across in the UK, so can't speak about from personal experience. Essentially it means that there's a combination of additives and minerals in the water that over a few days change sufficiently that water chemistry alters dramatically. Take a look here: http://www.wetwebmedia.com/FWSubWebindex/fwhardnessfaqs.htm Go specifically to the thread "pH/Ammonia Issue (RMF, never come across this, any ideas?)" and you'll see than Bob and I went over and over a similar issue with another a fishkeeper.> <<I have re-read... and have encountered such issues, vacillating GH, KH in tap/mains water supplies... As stated in the cited string above, there are municipalities that at times will run more of a few types of mainly "flocculants" (though other chemicals can/do have this and other "anomalous" effects)... And there are many cases of "bad readings", particularly for strip-type tests... and other endogenous factors can certainly cause wide and rapid shifts in hardness and pH... as is gone over... RMF>> I've read that certain conditioners for chlorine, Chloramine and ammonia will pose false positives for ammonia depending on the test kit used. <Correct. Test the tap water prior to adding anything. Any traces of ammonia will be dealt with via your additives, so shouldn't be an issue.> With Kordon's AmQuel as I can get the ammonia down to 0 for water changes (using twice the dosage amount, but reads for 1 ppm removal, since my tap comes out at 2 ppm, I'm assuming this is correct?). <Can't do any harm.> With Seachem's product, which says it treats for all the same, I can't get the level down to 0, in fact it doesn't budge the ammonia at all. <Your ammonia test kit will detect "false positives" from certain other chemicals, such as Chloramine and apparently Nessler's reagent.> Nor does it seem to adjust the pH based on my drip test (neither on water drawn and conditioned and tested immediately nor tested 24 hours later after being aerated). Another conditioner I tried this weekend will drop the ammonia to .25, but no less, no matter how much I add. Am I over dosing the conditioner? Am I correct to not add any water to my tank unless it reads 0 for ammonia? <<Yes! Best to treat, store "new" water outside the system... for a week if you can. RMF>> Can you best advice on how to stabilize my pH from here? Or ideas on to the cause and/or how to further test to determine what is going on? I've recently upgraded all filtration and moved the biological filtration to the new. However, it seems useless since my pH is so low. <OK, here would be my advice. Put the strip test kit to one side for now. I'm assuming it's an all-in-one strip, right? Let's assume these are mislead/unreliable when used with your tap water. Leave them for checking nitrite/nitrate levels at which they'll be fine and dandy. Good enough for making sure your water changes and filtration are doing their thing! Buy a carbonate hardness test kit and a pH test kit. These are the two critical ones for water chemistry. The general hardness test kit, though it sounds useful, actually has somewhat limited usefulness despite being "general". It doesn't really tell you anything about the ability of water to resist pH changes; only how much non-carbonate "stuff" is in the water. Since these minerals have near-zero impact on pH buffering, this isn't informative. Now, your carbonate hardness kit will test specifically for the carbonate and bicarbonate content of the water, and THIS is the stuff that keeps pH from changing. The aim for most freshwater fishkeeping is get a carbonate hardness of around 5 degrees dH (about 90 mg/l calcium carbonate equivalent). This amount should buffer against any reasonable amount of acidification between weekly water changes. If you find you don't have this amount of carbonate hardness, you'll need to add some to each new bucket of water. A good Malawi Cichlid salt mix will do the trick, though obviously there's no need to use the full dose. The usual ratio is: 1 teaspoon baking soda (sodium bicarbonate) 1 tablespoon Epsom salt (magnesium sulfate) 1 teaspoon marine salt mix (sodium chloride + trace elements) For a Malawi aquarium you'd add this to each 5 gallons/20 litres, but since we likely won't need nearly so much, try using one-fourth the amount to begin with, and if that doesn't work, one-half. So initially, 1/4th a teaspoon of baking soda, 1/4th tablespoon of Epsom salt, 1/4th teaspoon marine salt mix. This is clearly not an expensive way to go! But it works really well, and should fix the pH at around 7.5 plus or minus a little, and get you a carbonate hardness around the level we want. General hardness will be somewhere around 10 degrees dH, but it really doesn't matter that much. Add these salts to buckets of water prior to use, and ideally, leave the water overnight and then test the water chemistry (pH, carbonate hardness) again the first few times, just to see how things pan out. With luck, the Malawi mix will compensate for any funniness in the water as supplied by your water company. Problem solved.> The tanks have river rock, sand, slate, gravel, but nothing that I haven't bought at a LFS. <Cool.> Thanks again for any insight or instruction you can provide. Gina <Hope this helps, Neale.> <<I do agree with your "all fits" advice above... Starting with most any/all source water, the simple mix/addition should serve to bolster hardness, fix pH well enough... RMF>> Re: Have irreparably harmed my Cory? (RMF, would appreciate input) 3/10/09 Thanks, both of you. <Most welcome.> I've treated 5 gallons of tap water with Amquel and 1/4 tsp of each baking soda, Epsom salt and marine salt. I'll let it sit overnight with an airstone before I do a water change. <Quarter TABLESPOON of Epsom salt! Not teaspoon. No big deal this time around, but try and get it right next time, eh? Oh, by the way, one tablespoon is three teaspoons, so a quarter tablespoon would be 3/4ths of a teaspoon.> I got a carbonate hardness test as well. I already had liquid tests for pH and all the others. Although the numbers are a bit different, it seems to show the same trend as the strip test. <Good.> The 20 and 5 gallon tanks register a pH of 6, 0 mg/l. <Low; biological filtration operates best around 7.5-8, and below 6 stops altogether. So unless there's a darn good reason, a pH of 7 or slightly above is the ideal for community tanks.> The 40 gallon tank that was conditioned with Amquel and has been running fishless at 80 degrees with a pinch of food added daily, registers 50 mg/l and a pH of 7.2. This is after 5 days. My tap comes out 90 mg/l and a pH of 8. I have had a bucket of untouched tap water running with an airstone for close to two days and it still has the same readings. So I'm assuming around 4/5 days my carbonate hardness drops by half? I'll guess I'll keep testing the tap water and 40 gallon tank to see how fast it continues to drop. <If you add the carbonate hardness "recipe" suggested, my prediction will be that water chemistry in terms of pH will remain essentially stable between water changes. The higher the carbonate hardness, the less pH will drop. Hard, alkaline water (like in a hard freshwater aquarium) basically doesn't change at all, or if it does, by tiny amounts. See how the one-fourth dosage I've recommended works out; if it doesn't work, up the dosages to one-half dosages per bucket of water. Even at full dosage, it's would be ideal for things like livebearers, though soft water fish such as tetras might complain.> I'm assuming I won't see a jump in the pH or carbonate hardness with the Cichlid mix overnight ( in the treated change water) as it takes several days for it to drop. <Correct. And with increasing carbonate hardness, the rate at which pH drops will slow down.> Does that mean, it might be several days before I see a change in my 20 gallon tank? <Yes.> Is a 20% water change with the new mix, every day, too quick a change? Should I go slower than that? <This should be fine.> Also, Bob, had put a ?! next to my tap water ammonia reading of 2+. <This is for your tap water, right? Before treated with dechlorinator? The _maximum_ allowable level in drinking water is 0.5 mg/l, in the United Kingdom at least. Ammonia usually gets into drinking water via things like agricultural run-off. Do check with your water supplier what the ammonia content of the water supplied to you should be, and ask whether this reading is normal. There could be a problem. If you're detecting the ammonia AFTER adding dechlorinator, you're probably detecting Chloramine after treatment with dechlorinator. Provided the dechlorinator treats Chloramine, you can ignore this "false positive" reading for ammonia.> It's steadily at 2. Is this abnormal? <Yes; check with your water supplier.> I shower in the stuff and my dogs drink it. <Ammonia isn't especially toxic to humans at low doses (our bodies produce the stuff all the time) but it isn't normal to get this amount in drinking water. If you add water with ammonia at 2.0 mg/l to the aquarium, you're basically dumping a lot of pollution in there. While the filter will fix that problem reasonably quickly, for a short while at least the fish will be exposed to a serious toxin.> Eventually I would like to store water a week ahead as suggested, I tried it at the beginning of all this but after week the tap water still registered ammonia at 2. But at this point, I've read so much, I feel like I have too much information and not enough understanding. <<Ahh! A beginning for enlightenment. RMF>> <The addition of carbonate hardness to each batch of water should make the water chemistry problem go away. Trust me on this. As for the ammonia, that's a weird one. Some products such as Kordon AmQuel will remove ammonia from tap water, making it safe to use. Do see here: http://www.novalek.com/kordon/amquel/index.htm http://www.novalek.com/kordon/articles/insights_into_test_kits.htm Once your water is hardened and then treated for chlorine, Chloramine and ammonia, it should be ready to use. I can't see any further problems with your fishkeeping, and hope it will be a LOT SIMPLER after this.> I'll keep you updated on if this works for my system. If it does (fingers crossed) does this mean I should eliminate my Corydoras from my tanks since I am using a salt mixture to steady the chemistry? :( <Nope. The amount of carbonate hardness is low enough not to bother Corydoras, and the salinity trivially slow. To put this in context, seawater has 35 grammes per litre salt, which is almost 6 teaspoons per litre, or about 22 teaspoons per US gallon. The one-quarter teaspoon is as nothing by comparison.> Thanks again, Gina <Cheers, Neale>

Bronze Catfish disease, reproduction 02/12/06 Hi. I have six bronze cats which have are all happy and healthy. They play in groups in the bubbles and are very active. One of them laid eggs a couple of weeks ago and became very fat again looking like it was about to spawn but died very mysteriously. It was starting to look quite swollen and reddish around the lower belly. Has she died from not laying her eggs? Sorry to bother you but have tried Google with no luck. Thanks very much, Dave. <This fish might have been "egg-bound"... a condition where the eggs don't pass for a few possible reasons... or perhaps became infected in the area. Providing suitable water quality, nutrition avoids many of these incidents, but not all. Bob Fenner>

Corydoras panda are losing their eyes! 1/26/06 I hope someone can help. Recently I noticed 4 of my young pandas have lost their eyes. 2 have died so far. After they lose their eyes they start to loss their color and turn whitish. They still feed and act silly. I've had pandas for a few years and have managed to breed them very successfully. I love my little guys and take good care. Could this be a disease? <Not likely> or is someone attacking them? <Yes> The only "new" addition is a very young Kribensis Cichlid (about the same size as the pandas). I have a 60 gallon tank with mostly tetra (cardinals and hatchets), 5 Platies, 2 small angelfish, 2 yoyo loaches and 2 Plecos. <I suspect the Kribensis or loaches... but could be an angel... only close observation or systematic removal will reveal the culprit. Bob Fenner> Help me please - Sabiha

Cory Quarantine Query (Now say it 5 times fast!) 12/26/05 Hello~ <Hi.> A newbie in the field, but have been gleaning a lot of info from this site-very appreciative of all the knowledge that is accessible. <Outstanding, glad to hear we have been helpful.> I have a 12 gal going for about 3 months...all is fine, but spotted a few panda Corys that I would like to buy and QT- and all that I have running besides the 12gal is a 2 gal...would this be big enough <Enough.> for the Pandas (3) to spend about 2-3 weeks in before putting them in the larger tank? <2 gallons is pretty small, and I would be a lot more comfortable with something in at least the 5 gallon range. However of you plan to go ahead with it, the tank would need to be well filtered and have good surface area. Daily water changes of 30 to 50% would be a must.> Thank You Very Much, <Quite welcome.> Merry Christmas, <Ditto.> Judy <Adam J.>

Sick Cory catfish 11/14/05 I have a 10 gallon tank with 7 tetras and 3 Cory catfish. One of my catfish has been sick for 2 weeks. I expected him to die a while ago but he just keeps hanging on so I was hoping someone could give me advice on how I could help him get better. He swims around but then rests upside down. <Yikes, bad> He also will swim straight up to the top of the water and then float upside down back to the bottom. Its like he's lost his sense of balance. <Yes> He doesn't have any other symptoms except lying upside down. My water parameters are all normal. The temp. of the tank is 80 degrees. I'm thinking that he might have a swim bladder infection, <Likely some damage here, yes> but have no idea on how to treat it. I want to stay away from medication if possible. Any advice? Thanks! <I would at this point simply observe this fish and hope for a spontaneous cure. Bob Fenner>

Doomed Corydoras Hi WWM crew . . . haven't emailed you in a while (thankfully). My main problem is, that no matter how hard I try, my Cory cats never seem to prosper. It's so frustrating since Corys are my favorite fish. <Mine too> No matter what conditions I keep them in, they eventually die, lose their barbels, or remain stunted (never mature from 1 inch juveniles). I have acquired some beautiful harder-to-get species, such as similis "violet", xinguiensis, caudimaculatus, and trilineateus. I used to have six xinguensis (now five? or four?), and have two similis, caudimaculatus, and Trilineatus each. I assume that it is not for lack of company that they are dying. They seemed to lose their barbels on a Fluorite substrate, so I switched them to a bare-bottom tank. The current tank: 10 gallons, sponge-filtered, a few plastic plants, one female Betta, rather warm (80-82 degrees). Every so often one of them, such as the xingus, will die suddenly. I can transfer them to a currently empty 75 gallon tank . . . I just really really wish to breed them, see them grow up and prosper . . . and live. My problems that I can see is the warm water temp . . . the infrequent feeding . . . and the rather dirty tank bottom. Thanks for your time and info! <Arghhh, your breaking my heart. I love the little guys, their selfless devotion to cleaning your gravel, the way they wink at you when you stare at them long enough, ok I'm done. For starters, what are your water parameters? If you are serious about breeding them you will need to set up a tank for them, and them only. Like you said "warm water temp . . . the infrequent feeding . . . and the rather dirty tank bottom" this will cause problems. 82 is a little high, you will need to vary the temp depending upon the type of Cory, but high 70's is a good starting point. These guys love live worms, I feed mine shrimp/algae wafers and left over frozen food, but I am not trying to breed them. 10gal is a little small, a 20gal long is a good start. With good water quality and good food you should be ok. You might try starting with a more common Cory instead of shelling out the cash for the rare ones. Use the Google search tool on our site and google.com to find more information on Cory care and breeding. Good luck, Gage>
Re: the doomed Corydoras ... Thanks for the speedy reply! I have a few more questions to clarify, sorry. Will Corys be happy with members of other species? Should I get more of each species? As I said, I have several pairs of different species in my tank. This is because I bought them at a local aquarium society auction. This is great as there are many dedicated Cory breeders who can provide us with many healthy, rarer, and more-or-less cheap (about $3 each) specimens. The 10 gallon was intended to be a quarantine tank, but I don't want to move them to the 75 gallon, as they look so small and delicate. Perhaps I should add a small bio-wheel power filter? (I've got an extra one lying around) My water parameters are: nitrites - 20, and pH 7.8 (with "Amazon" buffer), KH 3, dh 2. My tap water is supposedly very soft, with no fluoride and hardly any (if at all) chlorine/chloramines. One of the perks of living in Hawaii! Of course the water is too warm <If I recall you mentioned your water was around 82, this is not terrible, but I would not go much higher> . . . Well I will do more water changes, feed them twice a day, <They love worms!> add a fan . . . and hopefully see them grow to 2 and 3 inch maturity. Thanks for your help . . . Trisha. <Hey Trisha, great idea with the QT tank, it's the only way to go. I would however add the filter (the more the merrier), and keep up on water changes. Nitrates are really high, they should be around 0 I am guessing that ammonia is high too. How long has the QT tank been set up? Sounds like it is rather new. I would still be sure to use some sort of water conditioner to remove chlorine and chloramines, your Amazon buffer may do this, I am not sure. What other fish do you have in the 75gal? These fish are pretty tough for their size. Corys will get along with other species of Corys, but would be happier with more of the same. In the wild they like to hang out in shoals of about 50, not always easy to recreate in the home aquarium. Gage>

Are my Corys stressed? Hi there, I'm new to tropical fish having had a cold water system for a few years. I have a small setup of about 8 (UK) gallons - yes I know it's odd! I'm currently cycling my system with 4 Trilineatus Corys. I've had them for a week now but I'm really worried that they're not happy. They don't stay at the bottom of the tank; they swim in the middle and up and down the sides of the tank and only go to the bottom when they're hungry. Now I've noticed that their gills are going pink. I've done ammonia tests and the levels are 0. What am I doing wrong? I don't want to lose them -they're too cute! Can you help please? Thanks, Sau <Hi Sau, Yes, if you are cycling your tank it is producing Ammonia and then nitrites, both of which are deadly to fish. Cycling means that the nitrogen cycle is establishing itself and producing these wastes. You should be testing for ammonia/nitrites and the final product nitrates. Please read more about the nitrogen cycle at WetWebMedia.com and perform regular water changes to relieve your fish from these wastes. This should help, Craig>
Re: are my Corys stressed? Hi Craig, Thanks for the advice, I'll get reading. Since last emailing, I've tested for ammonia, nitrite and Ph. Ammonia is 0 and Nitrite 0.1 and Ph is 8.6. Could the alkaline water be bothering them? Their gills are still pink. <These fish are sensitive to hard water. This may be your problem.> I also wonder why they are so jumpy. They flinch and hide every time I lift the hatch to feed them and swim up and down the front of the tank constantly. Do you think they're scared at the moment because there are not many fish in the tank? <No, I suspect nitrites, ammonia if there is nitrite, and also hard water indicated by 8.6pH. I was going to buy two more Corys this weekend so they had a bigger family to shoal with and perhaps not be so scared. Do you think this is a good idea? Thanks for helping, Sau <After addressing the current situation, yes, but I wouldn't until then. Check out http://www.wetwebmedia.com/FWSubWebIndex/callichthyids.htm There is lots of info you need there, especially health, source and water issues. Craig>

Sick Corydoras Catfish Hi, I have a question about what I think is a sick Corydoras cat fish. I have an eclipse six Marineland aquarium, started it in Oct. 2002. Right now I have 2 white clouds, 2 harlequin Rasboras, and 1 Cory cat. <Corydoras catfish should be kept in groups, and not in tanks this small. Do read here: http://www.wetwebmedia.com/FWSubWebIndex/callichthyids.htm> Everyone was doing great since Nov., but these past two weeks the Cory cat has been swimming erratically, gulping water at the top once a day or so. <His going to the surface to gulp air is normal for Corydoras species. If you have been at home more often than usual lately -- say, due to the winter holidays and time off from work/school -- could it be that you are simply watching the tank more often and thus noticing this behavior that was present all along?> He was fine before, eating every day, and almost never went to top to gulp for air, and would move about bottom. Now he doesn't eat, and he hides out in corner of tank, Very still, alive, but still. <What are you feeding him? These fish need meaty foods twice a day.> I had gotten some plants in from a place called aquabotics.com- <I'm not finding this e-tailer...> and they didn't really last the week- 1 java fern, 1 African bulb lace, and a Boca Carolina plant. I had purchased a live driftwood centerpiece the week before, and no problem. <I am guessing that by "live driftwood" you mean a piece of driftwood covered with plants? Did your Corydoras start acting oddly before or after you added this driftwood?> Only the Cory cat isn't doing well- After a weekly water change I got rid of all plants, and the water is totally clear. I had been using a product called Algone, which takes care of excess nitrite/nitrate and keeps water clean. They have a webpage and a few people I know use the stuff- just put packet in filter. I had some high nitrite/nitrate and used it, from decaying plants, and the tank was clean in a week. <When did you start using the Algone, compared to when the Corydoras started going downhill?> I haven't had any trouble with water in past 2-3 weeks: I have no ammonia readings, 0 on nitrate and nitrite readings. Ph is between 6.8-7.2 but Jersey water is hard. I had readings of 20 or 25 on KH and about 15 on GH. I bought an AquaPharm. tap water system, and now the KH is 11 and GH about 9. Water looks a lot clearer too. <Good> Like I said the other fish are great- but Cory, not so good. I don't know what else to test for. <Check the pH of the water coming out of the tap water purifier.> Is there any chance that the plants somehow affected the cat. <Perhaps not the plants themselves, but something carried in with the plants or driftwood.> Any other tests you can think of- he looks fine, no color change, or Ick or anything I can see. Just sits still and won't eat. I'm worried about him but don't know what else to do. <I would suggest weekly water changes (perhaps a half gallon or a gallon) to keep the water quality high.> thanks a lot Rosa Haritos PS- if he gets over this and is better, do you think it would help to get another Cory to keep him company? the clouds and Rasboras get along great- Or would 6 fish be too much for a 6 gallon tank? <Six fish would be too many for this tank. --Ananda >

Corydoras trilineatus losing colours Hello WWM Crew, I hope you can help with my problem, as nobody else seems to be able to. This is going to be a bit long, sorry. About two months ago I bought 5 c. trilineatus fish in a shop. By the time I got home, even before I put them in the tank, two of them were already half dead (sank to the bottom and could only swim a few inches at a time). After a day of realizing this was not only a shock of which they're going to recover, I ended their misery. Then a third one developed the same symptoms and I did the same. In a second visit to that same shop I've noticed that many fish were ill, or dead (and left in the tanks en masse) and so I never bought fish from them again. <Good plan!> I bought two other c. trilineatus in another shop whose fish look great, and they never had any problem. But that was just an exposition to the real problem. After about a week of having the two original surviving Corys, I noticed that one of them had a white patch just behind his gill. I couldn't remember if he always had it or whether it was something new so I decided to keep an eye on it. Now, after about two month, he has the same spot behind his other gill (which wasn't there before. The spot, not the gill. The gill was always there) <One would hope!> and the first spot is getting larger. He had a fin rot a while ago, which was treated with Melafix and is now completely healed, but I don't think it has anything to do with the spot as he had the spot first. Apart from the spot, he is okay. He swims with the rest of the Corys, he is active and he eats well. One more thing about him, which might be the clue to solve the mystery. He is kept with some guppies and some of the female guppies sometimes try to nibble on him. They don't really bite him, but the act if food is stuck to his body. They sometimes do it to the other Corys as well, but not as often, and while the other Corys just swim away immediately, this one "freezes" and only swims after few seconds. He has no wounds from those bites, but he seems to be shocked. <The guppies are feeding on flakes of skin> As for the tank, it is a 90 litres tank, with interior filter (Juwel compact), I change about 20% and clean the filter media weekly. The other fish in the tank are 6 guppies, one Betta male, and one Pleco. The water parameters are Ammonia 0ppm, Nitrite 0ppm, Nitrate 10ppm, temp 25.7c, pH 7.4, 17 dGH and 6 dKH. <All good> I know that the GH is too hard for Corys and that's my next project, but I more inclined into thinking that it's something that he got in the shop before I got him. <Maybe, it's possible that the hard water is stressing the Cory and lowering his immune system, but I think it's far more likely the bad conditions at the shop did that before you got him.> I attach two pictures of the fish so you can see exactly what I'm talking about. I hope you can help me identify the problem and find a treatment. Many thanks, Golan. <Hi Golan, Don here. Just a small point before getting to your main concern. Unless you're planning on breeding the Corys I wouldn't worry too much about your hardness. You could start doing water changes with RO/DI or bottled water, but that could change your pH. Not a bad thing, but it must be done slowly and kept steady. Better to have the fish adapt to your conditions then start tinkering with things, IMO. As to the white patch. It could be a fungus. I remembered a thread on this in our forum and found this. http://wetwebfotos.com/talk/thread.jsp?forum=3&thread=22384&message=179838&q=22576869746520706174636822#179838 Get's a bit off track, but I think you'll find it worth the time. Meds were recommended, but ended up not being needed in Gup's case. Since your water seems in line but the patch is spreading, I think medication is called for in your case. If you have a small tank you could use as a QT, move him there to treat. If not, it would be a good investment. If you treat your main, make sure you watch for ammonia and nitrite spikes and do water changes to keep them at zero. Don>

Cory melanistius Problems Hello WWM crew! Thanks again for having such an informative website. Over the past few weeks I've lost a total of 4 Corys. Three of the 4 that died lost all their black spots and black coloring on their dorsal fin, making them completely white...very strange. I'm guessing this happened once they already died because every day I observe all my fishes behavior and nothing seemed odd about any of their color. I've noticed on three of them that their gills looked a bit red, not swollen or anything just red or reddish. I was wondering if you could help me diagnose the problem. Here are my stats: 30G tank with a Penguin 280 filter 1 male Betta 5 cherry barbs 7 neon tetras 2 Cory cats :( I have all live plants w/approx 1 watt of light per gallon and 1 drop of Dupla plant 24 (fertilizer) every day: Green Cabomba (which was doing unbelievably well in the beginning, but has recently started to "break" at their stem segments leaving me half a stem floating in my tank, can this be a sign of changing water conditions?) Wisteria (doing very well, except I've noticed black algae with broad stringy arms on some of the leaves) hairgrass Mayaca Echinodorus tenellus pH 7 Ammonia 0 Nitrite 0 Nitrate ?? (I know I should be testing for it, but the LFS told me that my live plants would keep nitrates low to nil) GH 5 KH 1 Temp 29 C (I turned off my heater 2 weeks ago because I don't keep the AC on in the lounge room regularly, so this is just "room/water temp"). Maybe it's too warm for the cats? All my other fish are doing well. I figured if anything was really that bad my Neons would have been the first to react to it due to their sensitivity. I do a 20% water change every week. I feed my fish tetra flake food 1-2 times a day or I may substitute some frozen bloodworms for 1 of the feedings. Once or twice a week I would feed the cats Hikari sinking wafers to supplement. I'm not sure what I'm doing wrong, so please help. Thanks, Chris <<Hello Chris. A couple of things to consider. First, the LFS is wrong, plants will NOT leave your nitrates LOW TO NIL. What a load of horse hockey. The fact that your bio-load is low is the ONLY thing keeping your nitrates low. That is, IF they are indeed low. Chances are, they are not quite as low as you think they are. Buy yourself a NITRATE TEST KIT! The trick is in the balance between tank size and stocking rates. A large tank, say 75g, fully planted, with a dozen Neons, for example, may not have any trouble with nitrates. Yours will, if you don't already. Test your water! Another thing is, just how long has this tank been set-up? How often are you vacuuming the gravel? Try to do it at least twice a month, more often if possible, and be as thorough as you can. This is never easy in planted tanks. You might want to do a web search and read up on "anoxic substrate" problems. Cory cats can be quite sensitive to build-ups in planted tank anoxic substrates, normally they develop barbel disintegration problems, but worse things CAN happen... In which case, no, your Neons will not be the first to show a problem, the Corys will. I suspect your Corys are going to need a bit of intervention if you hope to keep any new additions alive. Always make sure you are buying healthy fish (I begin to doubt the quality of the LFS you are using...) Perhaps a quarantine tank will help. You can add a bit of salt which may cure any gill fluke problems. Yes, Corys CAN tolerate salt for short term medicinal purposes. Second, acclimate them properly: you don't mention your pH, is it vastly different from your LFS pH? And thirdly, if your tank is older than a few months, you may want to reconsider keeping Corys in this tank unless you can verify that the substrate isn't the problem. -Gwen>>
Cory melanistius Question Gwen, thank you for your response. I bought my nitrate test kit as you asked and my readings are between 0 and 12.5mg/l according to the TetraTest kit. Based on the coloration, my wife and I agree that it is probably about halfway or between 5-7mg/l. According to the instructions this measurement is acceptable, what do you think? To answer your follow-up questions: 1-The tank has been set-up for about 1.5 months 2-Along with my weekly 20% water changes, I also vacuum the gravel. 3-My pH is 7.0. I really hope I can keep Cory cats, they're so comical! Thanks again for your help. Chris <<Dear Chris; The nitrate level does sound acceptable. As I recall, the Corys you had were turning white and dying? Perhaps then, the fish were from rather poor stock, or being kept in poor conditions before you bought them. I am sure I mentioned a quarantine tank, I usually do :P It might be a good idea to set up a little 5 gallon q-tank for all new additions, that way you can treat them without worry, and if they are sick, you don't risk your entire display tank. Plus, it's WAY cheaper to medicate a five gallon than a larger tank. When buying new stock, always ask the store folks how long the Corys have been there, were they medicated for any reason, are they eating well, general health, etc. Yes, some stores are not honest, but many are. Again, the q-tank is your best insurance :) Check store Corys for barbel erosion, they should have long, healthy barbels. Stumpy snouts should be completely avoided. The fish should be energetic with full finnage, good color, and normal respiration. Avoid fish that continuously cruise up and down the glass, from the bottom of the tank to the surface, over and over. Corys DO swim to the surface from time to time for air, but fish that repeat the maneuver in a frenzied fashion are usually ill. Also avoid Corys who hide from the rest of the group, or seem in any way not overly strong. The clerk catching them for you should have a pretty good time trying to net them, a healthy Cory is a fast one :) Hope this helps. -Gwen>>

Cory Catfish problem Hi, I want to get some Cory catfish and I read that they could not tolerate any salt in their aquarium, but I also want to get Platies or mollies. < Cory cats come from the Amazon river basin where the water is very soft and somewhat acidic. The mollies and Platies come from Central America where the water has more minerals and salts. > I read that Platies and mollies need some salt, so is there any that I could have both in the same aquarium? < I have found that Platies are pretty tolerant of a wide range of water conditions and may be worth a try in your situation. Try and get half grown ones as they may be able to adapt to a wider range of water conditions. Mollies I have found truly do like some salt added to their water or they end up "shimmying" in the tank. There are a whole group of tetras worth looking at. Just try and get the ones that don't get too big. Barbs are fast moving fish that are fairly hardy but tend to be fin nippers, especially with your female Betta.> If not, what are some other fish that would substitute the Platies and mollies that would go well with female Bettas? Thanks for any information. < Check out the Rasboras too. These fish are from Asia and are attractive , don't get too big and will not bother the Cory cats. -Chuck>

Cory Catfish Question Hello, I have an Albino Cory catfish in a 42 gallon tank. It has been with the other fish for months, but this week I noticed that it was not down at the bottom like usual. Instead it is swimming at the top and floating around. It seems a bit sluggish in its swimming, but otherwise looks alright. My husband and I did a 30% water change last weekend which is consistent with what we have always done with this tank. > Do you have any ideas what might be up with my little fishy? I don't know if it is related or not, but we have had it for 4 or 5 months and it hasn't really gotten any bigger. He is about an inch long. > Thank you for your time and consideration. Anne > <<Dear Anne; In order to answer, I need to ask for your water test results. Do you test your water for ammonia, nitrite, and nitrate? I would need to know these levels. If you do not own your own test kits, please take a sample of your tank water to your LFS and have them test your water for the above. Please let me know the results. This is always the first thing to do when you develop a health problem in your tank. It does not matter which fish is affected, it has to start somewhere. So, I always ask for water test results first. IF all is well, it could be age, aggression, or some internal problem the fish has developed over time due to diet deficiencies, etc. Please let me know your test results first. Thank you, Gwen>> Hello Gwen, I got the test kits you recommended and I tested everything this afternoon. ph 6.4, ammonia 0, nitrite 0, nitrate ?? it was quite pink, but it was brighter than ones on the chart. I am guessing 50 or higher, but I am not quite sure. In any case, I guess I should do a water change tonight, shouldn't I. Anne <<Hello Anne, thanks for getting back to me. Yes, go ahead and do a water change. In fact, if possible, try to do a 20% water change every second day, to bring those nitrates down. Then you should test your water every other week to make sure the levels are not going back up. Buy a nitrate test kit, and do it yourself, it's really quite easy and saves you a trip to the store. Also, your Cory should start feeling better within a few days, and all your fish will live longer and healthier if you keep track of your levels :) If there are any other problems, please feel free to email me again. -Gwen>>
Cory Cat Thank you Gwen for all your advice. Unfortunately, the Cory cat died today. I will continue to do the tests you recommended, and get a few more Corys. Anne <<Hey, sorry to hear, Anne. I hope you will get more Corys. They are fun to watch and a joy to keep. Try not to be too bummed, though. You did a fine job trying to save him, but sometimes we just lose them and there is nothing we can do about it. I urge you to get some more, and try again. Best wishes -Gwen>>
"Cory Catfish Question" Greetings - I read with interest and anticipation Anne's question ( http://www.wetwebmedia.com/FWSubWebIndex/armoredcatfaqs.htm, "Cory Catfish Question") as she described the current behavior of one of my fish quite accurately. After weeks of wondering, reading, medicating and worrying, I thought to myself "Finally! The Answer!". Alas, it was not to be, as Anne's Cory expired before a full examination could be conducted. :-( Like Anne's, my fish is not staying down on the bottom as per usual. It is swimming, upside down, at the top of the tank and diving down to the bottom every once in a while. Until recently I thought it had trouble getting to the bottom, when I noticed that it sleeps on the bottom of the tank, so apparently not... Comparison with a like fish (I have two of the Albino Corys) shows that the one acting strangely has dark blotches inside its abdomen. Both fish seem to be a less active and less interested in food than I remember them being. Neither fish has grown much since I bought them.