Cory cats dying AGAIN

[parker002]

Tank Size: 55g
Age of the tank: 6 months
pH: !!! 8.4 !!!
Ammonia: 0
NitrAtes: less than 20
nitrites: 0
GH/KH: gH between 150-180, kH over 300
Temperature: 78F
Fish:

Symptoms:

My cory cats are dying again. One of them we in the filter intake this morning. Another is lethargic and laying on the bottom breathing heavy.

The only thing I did was add a couple of plants last night to prep for releasing the fry from the breeder net.

Can anybody help me? I'm ready to give up on this species altogether. Is it my substrate? Should I switch to a smaller substrate that's less porous?

Symptoms:

My cory cats are dying again. One of them we in the filter intake this morning. Another is lethargic and laying on the bottom breathing heavy.

The only thing I did was add a couple of plants last night to prep for releasing the fry from the breeder net.

Can anybody help me? I'm ready to give up on this species altogether. Is it my substrate? Should I switch to a smaller substrate that's less porous?

[Carl]

Sorry you are having so many difficulties with your Cory Cats.

How long have you had these Cory Cats?

Can you take a picture of your substrate, as it is possible that either there is a latent pathogen in the substrate and/or you might have some sort of sulfur reduction and other anaerobic activity going on (which can promote Aeromonas infections).

Medicated Baths may help, but based on this history this is more of “band aid” that likely is not going to solve this problem.

Since Cory Cats can be sensitive fish, your source for these may be in question.

I can say from experience that I too have had Cory Cats that will come in looking great, then start dying. Switching my source has often corrected this problem when other possibilities were exhausted.

I would also consider the use of UV Sterilization.

Carl

[pamc]

Sorry to hear the corries are not doing well, I have had similar issues with them and here is an experience to consider.
From your first post (I think I found it) the tank has been running since August 09 and you started having issues in Sept. 09. You posted the description of the loss of barbels and bottom portion tail fins; I would guess their bottom fins (anal, pectoral and ventral) look underdeveloped or thin, as well.

You have tried several different meds and methods of resolving an issue that you’re just not quite sure what it is, to be able to target it. I have done the same thing, so I am not condemning in any way. I have spent $$$ dollars treating a ten-gallon tank of corydoras.

Your tank can go bad for any reason imaginable. It may be a combination of things rather then just one thing. Take for example you have had meds in the tank in the early stages of the cycle, which may have thrown your cycle off. Usually a cycle can take up to three or more months to complete.
Based on the physical description of your corries (and a guess) and the meds in to the tank during the early cycle stage, I would say the surface bacteria with in the tank are also off balance.
Also not sure of the feeding habits, but if corries are not begging or in constant search of food, they are over feed and the excess food complicates the chemistry as well.

It was Carl’s mention of the anaerobic activity, the bacterium is found in the aquarium (usually lives in the substrate where there is no water flow or oxygen) but in small amounts. This suggests the good bacteria (forgot the name) have not been established in the substrate as anaerobic bacteria may have “taken over”. The establishment of the good bacteria could have been complicated by an incomplete cycle, a recycle, or by aggressive vacuuming (not sure if you did this, I did, but more is not always better) you might be burying debris, which is feeding this anaerobic bacterium. If this happens the anaerobic bacteria can cause, the parts of the corries bodies that are touching the substrate to erode. With that said, I am not sure if it is the bacteria itself touch the fish or a by-product it produces that causes the damage, so in my simple mind it is the one and same. Major health issues or infections will occur when the fins-barbels are eaten way to the base of the fish's body.

Keep a close eye on your basic tests (I know a pain in the rear) for awhile to confirm to yourself whether of not the tank is properly cycled and learn to do them right (maybe you do, I did not for my first year). As you are keeping bottom dwellers and want to provide them with suitable conditions, always pull your test sample water from the bottom of the tank. Keep cap on test tube as you lower it in the tank. Remove cap for filling when tube is resting on substrate, and then recap the tube once full. while it is still resting on the substrate, before bringing the tube up and out of the water. Surprised me on how differently the test results could vary based on what part of the water column you pulled test water from.

Personally, after tons of meds, I feel back to the old school of water changes. I did a lot of daily water changes; the de-chlorinated water was aged and aerated for 24 hrs prior to use. Daily water changes for about two weeks. Then reduced to every other day for a couple weeks and then every third day. Which is my standard routine. And yes, I lost a few of the corries along the way. Since then, I have read that some have used those bottles of bacteria to help balance/cycle their aquarium bacteria with good results, however I have never tried that.
I do wish you and your corries the best; they are by far some of the funniest little fish to watch.

[parker002]

Guys, I had sinus surgery yesterday so I'm not feeling up to much right now. I will read through your suggestions and respond as soon as I can. I did buy new substrate yesterday and intend to change it.

[Carl]

Jan 15, 2010 8:11:32 GMT -5 parker002 said:

Guys, I had sinus surgery yesterday so I'm not feeling up to much right now. I will read through your suggestions and respond as soon as I can. I did buy new substrate yesterday and intend to change it.

Sorry, I hope you recover quickly

I think the change of substrate is the best idea at this point, also consider a UV Sterilizer too.

Carl

[parker002]

OK, I added my water parameters to the initial post, primarily because my pH has spiked. It's been around 7.3 forever and all of the sudden today it is at the very high end of my test strip - around 8.4. I have no idea why.

Here's a couple of pics of my substrate:

[Carl]

Can you test your tap water for a comparison (if the test strips get moisture, their accuracy may suffer considerably)?

Although strips are generally not quite as accurate, they are still useful (I have used test strips for years in my maintenance business for the speed of these tests, and when compared to liquids, accuracy was not off by too much, usually less than 10%)

Assuming reasonable accuracy, a spike in pH can certainly cause problems if it happens quickly. A change from 7.3 to 8.4 is more than a 10 times multiplication in pH

The question is how, usually sudden pH swings are the other direction unless a water change is performed using water of a vastly different pH and KH.
What is your before and after KH as well as tap water KH?

As to your gravel, it is very polished in appearance which does not attract as much anaerobic bacteria as much more porous gravel can. As well your tank looks very clean

I wish I can say I see a "smoking gun" other than the pH swing (which again is an unusual swing upward unless the test strips were compromised)).

*I still would start with the substrate change
*As well, if you are still thinking of attempting Cory Cats again try a different source, or ask your local dealer if they can use a different source. As I noted earlier, I have seen first hand this take care of a Cory Cat die off problem as these fish often ship very poorly and can be suffering kidney damage from this which will go undetected until the failing or weak kidneys allow a fatal infection to take hold (possibly from anaerobic bacteria in the gravel as suggested by pamc)
* A UV Sterilizer can also help with prevention and improve Redox as well, although a Sterilizer will not help with poorly shipped or otherwise weak fish (outside of improving the Redox Balance)

Carl

[fishfever]

Your tank looks good and your substrate looks nice as well. I suspect your stock may have not been so healthy to start with although it be a combination of things as well. That pH jump is rather odd because usually organic buildup tends to cause pH to drift down slowly. Is your tap water pH stable? I found mine to be quite stable (albeit very soft and low pH) but I know what it takes to fix it on each water change so I don't bother to test the tap water. If you suspect your tap water might be inconsistent it may be a good idea to test a sample before each water change.

I have had 3 of my cories for about 9-10 months and one for about 3-4 months. I am hoping I'm over the danger hump at this point and they all seem fine so far. I have had one develop a fungus growth at the base of his dorsal fin twice but MB/salt baths took care of it. One had one of his barbels missing when we first got it and it never grew back but it doesn't seem to miss it much. My substrate is similar to yours (including depth) although your gravel is slightly larger and more rounded (probably better for cories than mine). I do have a UV sterilizer installed (and it was in the tank when the cories were first introduced). I have used Wonder shells regularly for about a year since my water is so soft. I try to keep my pH as close to 7.2 using pH as possible (by adding pH buffer with each water change) but don't chase it. Since cories and tetras are somewhat salt sensitive, I use about 2 tsp per 5g of water. My heater keeps the tank at around 79 year round. Have you used any meds recently (cories can be sensitive to a lot of them)? It sounds like you are doing everything you to provide a good environment for the cories so most likely the stock you started with had issues.

[babygeige]

Something else to consider that the guy at the LFS told me when I was having cory troubles: Since they like to zip up to the surface to breath, if you're a big user of stuff like Febreze in the room the tank is in, it could be making them ill. He also mentioned carpet spray, like for pet dander. Not sure if that's 100% accurate, but it does make sense when you think about it.

[Carl]

Jan 19, 2010 23:16:38 GMT -5 babygeige said:

Something else to consider that the guy at the LFS told me when I was having cory troubles: Since they like to zip up to the surface to breath, if you're a big user of stuff like Febreze in the room the tank is in, it could be making them ill. He also mentioned carpet spray, like for pet dander. Not sure if that's 100% accurate, but it does make sense when you think about it.

At this point I think all ideas are worth considering

If anything like this is being used, I would suspend the use of it.

Otherwise I would sum it up with a change in stock source, change in substrate, and addtion of a UV Sterilizer and regular addition of positive mineral cations

Carl

[parker002]

My tap water is usually very pH stable and quite hard. Unfortunately, we've had alot of snow recently and now it's raining and that causes spikes in pH in the ground water supply. I'm riding it out right now - I'm still not well enough to do anything about it.

[Carl]

Jan 23, 2010 0:49:04 GMT -5 parker002 said:

I'm still not well enough to do anything about it.

I hope you do not have anything too serious and feel better soon!

Carl

[parker002]

Jan 23, 2010 11:28:15 GMT -5 Carl said:

Jan 23, 2010 0:49:04 GMT -5 parker002 said:

I'm still not well enough to do anything about it.

I hope you do not have anything too serious and feel better soon!

Carl

Not serious, no. I had my 3rd sinus surgery in 5 years and this time had ear tubes put in as well. Tired of the constant respiratory infections. At any rate, I have healed enough to get some things done.

Firstly, we replaced our substrate. We swapped out the large stone for 50 pounds of what I would consider "normal" (aka small) epoxy-coated aquarium gravel - Top Fin "Classic Beach".

There's no place for new fry to hide in the rock now, so that's good. Also, I like the way it looks and handles better. My plants are easier to work with and position after a water change. Plus, my daughter says it just looks more natural with the smaller fish.

Second, we did a 15-gallon water change using 10 gallons of distilled water and 5 gallons of tap water. I added aquarium salt since we used distilled water, but I couldn't use that much tap water with all the run-off we've had.

Current water parameters look very good. gH is over 180 and kH is over 240. pH is back down to about 7.3 or 7.4. The fish seem happy and healthy.

However, one of the 3 remaining cory cats has a lesion on his nose. I've resigned myself to the fact that they're going to die. I've lost any passion I had for the species, unfortunately. I'm doing what I can to help them, but it all just seems for naught.

Finally, we released our fry! They're doing well and the other fish aren't being aggressive at all. The tank is looking well.
---

[Carl]

First I am sorry to read about your constant respiratory infections; i hope you are done with these problems after this surgery.

I also understand losing your passion for keeping Corys; maybe someday in the future you can try again, but with a different source.

Carl

[parker002]

Yeah, I'm actually feeling great and boy, it feels good to be able to breathe through my nose!

We lost another cory 2 days ago - we're down to just two. I've come to terms with it finally. It helps that we've got a dozen fry that are spritely and fun.

[sherry]

i have given up on on cory's to, Only have had three but neither of them have done well, seems like they always have an out break of some sort a few days after I get them.... I give up!

[parker002]

Feb 5, 2010 14:16:11 GMT -5 sherry said:

i have given up on on cory's to, Only have had three but neither of them have done well, seems like they always have an out break of some sort a few days after I get them.... I give up!

I lost another one 2 days ago. I'm down to one, and when he's gone, that's it for me owning them. It's just too much stress - I love the little guys but I can't bear to watch them die.

Ironically, the one I have left is the VERY FIRST one I bought.

I've had this tank since September. In total, I've lost 7 cory cats. The first group to die were in the tank almost 8 weeks. This second group that died were actually purchased in November, so as you can see, it's not like they died during the acclimation process. I also lost 3 oto cats and a pleco that was in the tank over a month.

By comparison, I've lost 2 guppies in that same time span. The two guppies died within 48 hours of purchase and could have either already been sick or just could not handle the change. The female molly that died, died within the first week.

The only non-bottom feeder that's died after being in the tank more than a week is my male sailfin molly. He was one of the first fish we ever bought. He lived through my 10G tank continuously cycling (we were naive then) and he lived through this current 55G tank cycling too. He was probably 1.5 years old and they really only live 2 years anyway.

Needless to say, my experience is that bottom feeders are just WAY too sensitive for my taste/skill.

[babygeige]

I'm in the same boat as you, parker02!! I went through probably a dozen in a year and didn't manage to keep any past about 2 months. I bought them from 3 different vendors at different times and lost them all, most with no warning at all.

I will be trying my hand at them again before too long since I adopted one from a neglected tank. I've had him for almost 2 months, so I've got my fingers crossed, lol. If it ever gets a bit warmer out and less snowy, I'm going to get him some friends.

I had the same problem with otos too.

[parker002]

I just did my first water change since going with the smaller gravel and I'm really glad that I changed out the rock.

1) Cleaning the smaller rock is far less disruptive for the ornaments/plants. I can clean all around them and barely disturb them. Rather than having to reposition EVERYTHING, as I used to have to do, I only had to "re-plant" one plant after cleaning.

2) My substrate wasn't nearly as dirty and I removed probably 75% less organic sludge than normal. I'm pretty sure that the reason for this is that food settles to the bottom and sits on top of the rock, where the mollies eat it. With the old, bigger stones, food would settle IN BETWEEN the stones, out of reach of the fish, resulting in more decaying organic matter in the substrate.

3) My gravel vac has an oval-shaped attachment that used to just get in the way. Using it today, I found that the attachment produced an interesting "flow" which ultimately resulted in pushing gravel from the top down to the bottom and pulling gravel from the bottom and allowing it to settle on top. Almost like "tilling" my rock. I have nothing other than a gut feeling, but I have to think that this is a good thing.

On a somewhat-related-but-lighter side note, just as I have resigned myself to the fact that I just can't keep bottom-feeders, I have also come to the conclusion that I will eventually be overrun with mollies.

When I removed the filter media from one of my filters today, it dumped a dozen fry about 3mm long (couldn't be more than 48 hours old!) into the tank. I removed the filter media from both housings and found 3 more still in there. Luckily, most of them became lunch, but a couple survived. I removed the large substrate and they ended up in the filter!

[sherry]

I have one left that has lasted a little longer then the other two, so we will see, how long he makes it.