DEATH: corydoras hasbosus or pygmaeus?

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ElanaJoy

Aquarium Advice Regular
Joined
Mar 14, 2016
Messages
58
Hi. I just started to stock my 5 gallon (yes, I know it's small) with corydoras hasbrosus. This is a newer tank, and my PH is high, like 8.2! I was told by my LFS that they would adapt. I dripped acclimated them over 6 hours. I added them to the tank, and the largest one died maybe 10-12 hours later. I am assuming it couldn't adjust? It was resting on a plant near the surface... :( wanting to get out of the water??? The other two seem fine, but I don't know what the warning signs are.

Should I try to lower my PH with peat?
Should I switch them for pygmaeus? Are they hardier?

I was initially going to go with pygmaeus after research, but the hasbrosus are so cute and the LFS guy said either would be fine.

He also suggested one species. But will they school together? There were only 3 of each at the store.

Also, the temp is on the low end but I assume still ok for them at 70.

Any thought welcome! Thanks!!!
 
I don't know a lot about catfish, so I can't answer any of those questions.

You'll hear people say that larger tanks are easier to maintain than small ones. When there are only five gallons of water, the percentage of water that becomes toxic rises a lot more quickly than 10 or 50.

Trying to change your pH can cause a lot of problems. You may want to cut your water change water with reverse osmosis water, but really a stable pH is most important.

And some fish adapt, but they won't thrive. It would be best to look for fish that thrive in a high pH environment.

70° F is pretty cold. Many community tanks are kept at 78° F.

Have you cycled your tank?

Welcome to the site.
 
I don't know a lot about catfish, so I can't answer any of those questions.

You'll hear people say that larger tanks are easier to maintain than small ones. When there are only five gallons of water, the percentage of water that becomes toxic rises a lot more quickly than 10 or 50.

Trying to change your pH can cause a lot of problems. You may want to cut your water change water with reverse osmosis water, but really a stable pH is most important.

And some fish adapt, but they won't thrive. It would be best to look for fish that thrive in a high pH environment.

70° F is pretty cold. Many community tanks are kept at 78° F.

Have you cycled your tank?

Welcome to the site.


Thanks, yes, the tank is cycled. Things haven't gone as smoothly as I would have liked. I did a fishless cycle, then waited for the fish to be in stock, checked with an ammo bump to make sure it was still cycled, did a 100% water change to bring down nitrates and switched from gravel to sand, put a stocking full of gravel on the sand, maybe added a small amount of ammo while still waiting for my fish to keep bacteria alive, then added my female betta for 2 days... just finally added fish yesterday. I feel like my ph was lower before the gravel to sand switch. it's PFS... I thought that wouldn't affect it. Those cories say 68-78 degrees. .... the others still look okay so far. I had a tiny heater, but I'm letting my friend with a sick betta borrow it.

I know everything I have read says stable PH is better than ideal PH. I don't know if I should try to add natural things to bring it down. They also like tannins, so maybe peat would be good...
 
I have a normal PH of 8.4, and have several species of corydoras. They're normally tank raised fish and can acclimate to most water types. I don't think it was your PH that killed it. So here, I have to ask 2 questions, sorry: was your tank properly cycled before adding fish; does your fish store have a return policy. Most reputable stores will refund or exchange fish within 2-4 weeks, depending on store policy, so you could probably take it back.
Most corydoras species are extremely tolerant of each other, but normally won't school together. The schools may intermix, but when they separate, each fish goes with its respective school.
 
I have a normal PH of 8.4, and have several species of corydoras. They're normally tank raised fish and can acclimate to most water types. I don't think it was your PH that killed it. So here, I have to ask 2 questions, sorry: was your tank properly cycled before adding fish; does your fish store have a return policy. Most reputable stores will refund or exchange fish within 2-4 weeks, depending on store policy, so you could probably take it back.
Most corydoras species are extremely tolerant of each other, but normally won't school together. The schools may intermix, but when they separate, each fish goes with its respective school.

Thanks you for your response. Yes, I did a fishless cycle with amonia. It was processing 4ppm in less than 24 hrs eventually. But in my response to Nirbhao, I explained it in more detail. Do you think I should have acclimated it more gradually? Also, is it normal for you to see your corys go up everyonce in a while to the surface, or is that and indication that there is not enough oxygen or something?
 
Also, is it normal for you to see your corys go up everyonce in a while to the surface, or is that and indication that there is not enough oxygen or something?

That is 100% normal corycat behaviour. mine alternate between sitting on the bottom - swimming around the tank at speed in a group, and occassionally darting up to the top as if taking a gasp of air and then back down again. Fantastic to watch :lol:
 
Lev is correct. They do dart to the surface periodically for a gulp of air. In fact, if kept in a tank with no way to reach the surface, Corydoras will quite literally drown.
I think you probably cycled your tank fine. I should've read nirbhao's answer and your response better.
It sometimes happens that a new fish dies during acclimation, or shortly after being added to a new tank. I doubt it was anything you did.
 
Lev is correct. They do dart to the surface periodically for a gulp of air. In fact, if kept in a tank with no way to reach the surface, Corydoras will quite literally drown.
I think you probably cycled your tank fine. I should've read nirbhao's answer and your response better.
It sometimes happens that a new fish dies during acclimation, or shortly after being added to a new tank. I doubt it was anything you did.

Oh, reading that has made me feel better. I have had significant luck with bettas, but I know they are pretty hearty, and I have never had a cycled tank before. Another question while I have you all: how important is a water conditioner if I am using a mix of spring bottled water and my well water? Because I didn't add any to this water! If I should add it, do I put it right in the tank? Does it go bad? I have an older bottle...
 
You mentioned something about changing the substrate to sand? Sometimes that will remove a portion of BB enough to cause a mini cycle and your parameters can go out of safe zone because of it.

As for the use of water conditioners, you should consider the issues of heavy metals in the water from the well. Especially important with shrimp or other delicate fish. Cory Habrosus are a little sensitive when there are a bunch of changes, like coming home , getting acclimated and going into a new tank. Then how many changes right before that with the shipping and maybe being shipped before that from an importer or breeder as well, they need a frequent supply of chow, I think that being smaller they do best when getting a little something to eat most every day.

I would add a nice large chunk of Mopani DW to really darken the water. You can also do some adjustments to your water more naturally by using RO/DI Reverse Osmosis/DeIonized wter available from a fish store most commonly stores with SW, and around here costs 50 cents a gallon. Usually the stores sell the 5G water storage containers, I personally like the rigid plastic much more than the soft collapsible kind.

Just substitute 25% with your tap (well) water, then check the pH, and if not to around 7.5 pH, try a 33% and so on using a gallon water quantity with new water each time. Then you will easily be able to get a good pH combination for your water changes. No tricky chemical changes from a bottle.

If it makes $ sense to you, you can always buy a small RO unit and use a storage container in the garage or a trash can in a utility closet to store it for wter changes. You could also preload the container with some Mopani wood.

The expiration date should be on the bottle somewhere. Maybe just for comfort sake get a new bottle. Check on the new purchase whether or not it binds/detoxifies heavy metals. I always use the conditioner in a container before I put it into the tank but if you want to put it into the tank dose for the volume of gallons in the tank and filter.

A side note, not necessarily needed by you but maybe other reading through, that not all water dechlorinaters even can bind neutralize chloramines, and if so a higher dosage is needed ofter double normal, and not all water conditioners or called water treatment are actually dechlorinaters. Not all will bind heavy metals either and some will bind ammonia and Nitrates and Nitrites as well like Prime to keep the tank safer, or be able to treat emergency issues. So read the label thoroughly know what you are buying.
 
You mentioned something about changing the substrate to sand? Sometimes that will remove a portion of BB enough to cause a mini cycle and your parameters can go out of safe zone because of it.

As for the use of water conditioners, you should consider the issues of heavy metals in the water from the well. Especially important with shrimp or other delicate fish. Cory Habrosus are a little sensitive when there are a bunch of changes, like coming home , getting acclimated and going into a new tank. Then how many changes right before that with the shipping and maybe being shipped before that from an importer or breeder as well, they need a frequent supply of chow, I think that being smaller they do best when getting a little something to eat most every day.

I would add a nice large chunk of Mopani DW to really darken the water. You can also do some adjustments to your water more naturally by using RO/DI Reverse Osmosis/DeIonized wter available from a fish store most commonly stores with SW, and around here costs 50 cents a gallon. Usually the stores sell the 5G water storage containers, I personally like the rigid plastic much more than the soft collapsible kind.

Just substitute 25% with your tap (well) water, then check the pH, and if not to around 7.5 pH, try a 33% and so on using a gallon water quantity with new water each time. Then you will easily be able to get a good pH combination for your water changes. No tricky chemical changes from a bottle.

If it makes $ sense to you, you can always buy a small RO unit and use a storage container in the garage or a trash can in a utility closet to store it for wter changes. You could also preload the container with some Mopani wood.

The expiration date should be on the bottle somewhere. Maybe just for comfort sake get a new bottle. Check on the new purchase whether or not it binds/detoxifies heavy metals. I always use the conditioner in a container before I put it into the tank but if you want to put it into the tank dose for the volume of gallons in the tank and filter.

A side note, not necessarily needed by you but maybe other reading through, that not all water dechlorinaters even can bind neutralize chloramines, and if so a higher dosage is needed ofter double normal, and not all water conditioners or called water treatment are actually dechlorinaters. Not all will bind heavy metals either and some will bind ammonia and Nitrates and Nitrites as well like Prime to keep the tank safer, or be able to treat emergency issues. So read the label thoroughly know what you are buying.


Thanks you so much for such detailed info! I just read that fluctuations of .3 in PH in less than 24hrs can be lethal to fish. I'm going to assume that the cory who died just couldn't adjust. As for heavy metals, I asked my husband who seems to recall we got it tested and only were told we had high calcium. Maybe I can find a way to test it again.
 
I have acclimated fish to my water from my friends which hers was over 8 pH, and mine right at 6.8 pH. It was in an hour or 2. None dead. Some fish can adapt better to changes.

Delicate fish can be delicate, and fish who have had a hard couple weeks traveling everywhere and are stressed can die, and maybe as you said he just couldn't handle it. If he was that big, maybe he was very much older and at the end of his life anyway.

If you do not have more deaths, as in not an illness thing, you are probably going to have the best bet if you cut the water with RO and try the DW approach..

Also maybe find out where they came from, like locally bred, or from a huge fish farm, or wild caught. Wild caught are most critical in possibility of issues becasue of where they were raised, in softer water from their natural habitat. They are great little fish. Just make sure you see that they are getting food. Other bigger fish can sometimes bully them away.
 
I have acclimated fish to my water from my friends which hers was over 8 pH, and mine right at 6.8 pH. It was in an hour or 2. None dead. Some fish can adapt better to changes.

Delicate fish can be delicate, and fish who have had a hard couple weeks traveling everywhere and are stressed can die, and maybe as you said he just couldn't handle it. If he was that big, maybe he was very much older and at the end of his life anyway.

If you do not have more deaths, as in not an illness thing, you are probably going to have the best bet if you cut the water with RO and try the DW approach..

Also maybe find out where they came from, like locally bred, or from a huge fish farm, or wild caught. Wild caught are most critical in possibility of issues becasue of where they were raised, in softer water from their natural habitat. They are great little fish. Just make sure you see that they are getting food. Other bigger fish can sometimes bully them away.

Thank you again Autumn Sky. You are proving to be a valuable advisor! :) And now we have a conversation up about my CPDs too. I got them from the same place. Fairly reputable (and expensive!) fish store in Greenwich, CT, about 40 minutes from me. I know they will replace it for me when/if they get more in...or I could get the 3 pygmaeus??? There is a small piece of driftwood in there. Maybe I should figure out what kind. I could get another one... or what are your thoughts on peat moss?? I know the CPDs and the corys would like tannin stained water anyways, and I'm sure the betta would be happy too. What direction to go in? I'm guessing whatever I do, do so gradually? I am sort of afraid to do anything at the moment because I don't want to throw at them too many changes at once. I keep reading stable PH is more crucial than ideal PH.
 
For five gallons, it seems like it would be more economically sound to buy RO/DI water than an RO/DI system.

In the case of not being any where near a lfs which has water. I have a 30-45 min or more drive to get to stores which have it so the difficulty of getting to where it to pick it up and cost of gas can add up. I still drive for mine and have 4 containers for water (SW though). Having a unit can be such a great convenience and comfort knowing you didn't run out of water. There are some lower cost ones.
~~~

I feel that the Pygmaeus Cories, accounts from keepers (I don't and haven't ever had Pygmies) are that they are easier, and very hearty.
 
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