Cory Catfish not doing well . . . Someone help!!!!

[MeredithW]

I just wanted to add that water changes are an aquarium hobbyist's best friend. I've found few things in the fish world that cannot be fixed with large and frequent water changes. The old adage "the solution to pollution is dilution" holds quite true in the aquarium world. Fish produce waste which builds up very rapidly in an "uncycled" tank. Unless your tank has an established bacterial colony, the waste is not processed and continues to build up. When you add a lot of fish in a short period of time, you are not allowing the bacteria sufficient time to build to levels that would detoxify the ammonia in their waste. You need to be doing large frequent water changes until the tank has time to "cycle". This will dilute the ammonia/nitrite/nitrates, which are harmful to your fish AND create the perfect conditions for algal growth. This is doubly important in a smaller tank.

All I can say is that you know a lot more about fish than me! I need to get researching!

 

[Ol Grey Mare]

All I can say is that you know a lot more about fish than me! I need to get researching!

The aquarium hobby is a fascinating one, and one that I believe you are never fully done learning about no matter how much learning you do. Do you have a good local fish store - not just a PetCo type place, but the type of store that you walk in, look around and know "these people know fish"? That can be the best thing for a new fish keeper to find. Finding a good mentor that can be there with hands on/eyes on ability to help you sort through the various ups and downs that will come in the first several months can be a lifesaver.

 

[Ol Grey Mare]

Incidentally, one thing that you'll want to consider moving forward is that a lone cory cat is not a happy cory cat. This leads to the next issue - cory cats are best kept in social groupings, but you run into the issue of the limiting factor of having a small tank to work with in your stocking decisions. Once you get things sorted out and the tank has been able to properly cycle and is biologically stable THEN you want to up your cory population to at least 6. They bring very little bio-load to a tank, so even with a small tank like your 10 gallon I don't think this is going to pose a problem - until/unless you start making changes to the rest of the stocking in the tank.

 

[Rowsdower]

The aquarium hobby is a fascinating one, and one that I believe you are never fully done learning about no matter how much learning you do.

That and these darned whippersnappers keep changing the rules, techniques, and equipment.

 

[Rowsdower]

All I can say is that you know a lot more about fish than me! I need to get researching!

And there's plenty of research to be had. Incidentally, we still don't know if the Algaefix was the cause of your Cory's behavior. It could be that the same thing that is causing your algae bloom, excess toxins in the tank, is also causing the fish's symptoms. Most fish shops will do free or cheap water tests if you ask. It would be a good excuse to poke around and see what kind of resources you can find in your area. Don't let them tell you that the water is "good or bad", get the specific numbers if you can. And DO NOT let them sell you anything to add to your water to bring the ammonia down.

 

[MeredithW]

And there's plenty of research to be had. Incidentally, we still don't know if the Algaefix was the cause of your Cory's behavior. It could be that the same thing that is causing your algae bloom, excess toxins in the tank, is also causing the fish's symptoms. Most fish shops will do free or cheap water tests if you ask. It would be a good excuse to poke around and see what kind of resources you can find in your area. Don't let them tell you that the water is "good or bad", get the specific numbers if you can. And DO NOT let them sell you anything to add to your water to bring the ammonia down.

Ok. I will look into that. Thank you

 

[MeredithW]

Incidentally, one thing that you'll want to consider moving forward is that a lone cory cat is not a happy cory cat. This leads to the next issue - cory cats are best kept in social groupings, but you run into the issue of the limiting factor of having a small tank to work with in your stocking decisions. Once you get things sorted out and the tank has been able to properly cycle and is biologically stable THEN you want to up your cory population to at least 6. They bring very little bio-load to a tank, so even with a small tank like your 10 gallon I don't think this is going to pose a problem - until/unless you start making changes to the rest of the stocking in the tank.

I have two cories right now . . . I was thinking about getting some more . . . but someone said that you could have only one fish per gallon . . . is that true?? So far I have eight fish . . .

 

[drumstick diva]

Ol Grey Mare, you are so knowledgeable, in countless areas ,I love to read your posts. I don't even have fish but always want to know what you have to say.

Bravo

 

[Bunnylady]

Quote: Gads, is that "rule" still making the rounds? I heard that when I was a kid!

The problem of how many fish a tank can safely hold is not a simple one. There are a number of limiting factors, including the amount of dissolved oxygen in the water and the ability of the biological elements in the system to safely process the waste. Another rule I have heard is based on the number of square inches of water surface (has to do with the ability to absorb oxygen out of the air), but the ability of the water to hold oxygen changes with the temperature, and moving the water with a filter and/or bubbling aeration can boost the the rate at which the water can absorb oxygen. Another rule says "one inch of fish per gallon;" the idea being that larger fish need more area, but that doesn't really cover the situation, either. If you think about it, one 6" Oscar has a great deal more mass than 6 inches' worth of Neon Tetras, and would generate a lot more waste and probably need a lot more oxygen.

And then you get into the actual oxygen requirements of the particular fish. Cory cats get part of their oxygen directly from the air (have you seen your Cory's dart to the surface for a fresh bubble?), so they can tolerate water with a lower oxygen content than some other types of fish. Labyrinth fish get all of their oxygen from air, which is why pet shops can keep Bettas in those tiny little bowls like wine glasses. Goldfish require quite a bit of oxygen, and cooler water can hold more, so goldfish that are perfectly happy in their tank at 60o F may be gulping air at the surface at 90o.

There just aren't any hard-and-fast rules about how many fish you can put in a tank. Basically, it boils down to maintenance. As I said, filtration and the use of airstones can boost the ability of a given amount of water to absorb oxygen. But even a tank that has water moving like a mountain stream still has only so much water in it, and the waste produced by the fish has to go somewhere. That's where the water changes that Rowsdower was talking about come in. When you remove water from the tank, you remove the waste products that are dissolved in it. Fresh water doesn't have the waste dissolved in it, so adding new water effectively dilutes the amount of waste in the water in the tank as a whole. How much waste the fish in the tank produce will determine how often the water needs to be removed and replaced to keep the amount of dissolved waste at a safe level for the fish. More fish = more waste = more frequent water changes. Of course, you want to make sure that the water you are adding is safe for the fish - water from some sources may need certain types of treatment to remove harmful elements before it is added to the tank, or it can be just as dangerous to the fish as the dissolved waste.

 

[Ol Grey Mare]

Gads, is that "rule" still making the rounds? I heard that when I was a kid!

The problem of how many fish a tank can safely hold is not a simple one. There are a number of limiting factors, including the amount of dissolved oxygen in the water and the ability of the biological elements in the system to safely process the waste. Another rule I have heard is based on the number of square inches of water surface (has to do with the ability to absorb oxygen out of the air), but the ability of the water to hold oxygen changes with the temperature, and moving the water with a filter and/or bubbling aeration can boost the the rate at which the water can absorb oxygen. Another rule says "one inch of fish per gallon;" the idea being that larger fish need more area, but that doesn't really cover the situation, either. If you think about it, one 6" Oscar has a great deal more mass than 6 inches' worth of Neon Tetras, and would generate a lot more waste and probably need a lot more oxygen.

And then you get into the actual oxygen requirements of the particular fish. Cory cats get part of their oxygen directly from the air (have you seen your Cory's dart to the surface for a fresh bubble?), so they can tolerate water with a lower oxygen content than some other types of fish. Labyrinth fish get all of their oxygen from air, which is why pet shops can keep Bettas in those tiny little bowls like wine glasses. Goldfish require quite a bit of oxygen, and cooler water can hold more, so goldfish that are perfectly happy in their tank at 60o F may be gulping air at the surface at 90o.

There just aren't any hard-and-fast rules about how many fish you can put in a tank. Basically, it boils down to maintenance. As I said, filtration and the use of airstones can boost the ability of a given amount of water to absorb oxygen. But even a tank that has water moving like a mountain stream still has only so much water in it, and the waste produced by the fish has to go somewhere. That's where the water changes that Rowsdower was talking about come in. When you remove water from the tank, you remove the waste products that are dissolved in it. Fresh water doesn't have the waste dissolved in it, so adding new water effectively dilutes the amount of waste in the water in the tank as a whole. How much waste the fish in the tank produce will determine how often the water needs to be removed and replaced to keep the amount of dissolved waste at a safe level for the fish. More fish = more waste = more frequent water changes. Of course, you want to make sure that the water you are adding is safe for the fish - water from some sources may need certain types of treatment to remove harmful elements before it is added to the tank, or it can be just as dangerous to the fish as the dissolved waste.

Well, you just saved me the trouble of typing all that up

These are just some of the considerations that must go into stocking decisions - unfortunately it is far more involved than a simple fish/gallon equation.

ETA - in addition to the considerations that impact water quality - stocking choices must be made on compatibility for water temperature and conditions beyond keeping the water at healthy levels - species have varying needs for the Ph, water hardness, etc., current type, temperament, etc. Then you have to consider where, in the water column, particular species will primarily reside. After all, you could be within the old (incorrect) guideline of inches of fish per gallon, but if every inch of those fish is occupying only the top 1/3 of the tank you would still be grossly overcrowded.....finding that balance between those that are bottom dwellers and those that occupy the different parts of the tank will give you a happy, healthy community of fish and a much more attractive tank to look at.

I would suggest, OP, that you focus on getting over this initial hump with the tank and once it becomes balanced you really need to step back and decide what one fish species you MOST want to have in the tank - take your water to the LFS and have it tested so you know what parameters you are working with - this will dictate the overall conditions you will need to maintain and from there you can stock the tank with appropriate tank mates that will compliment the fish you have chosen in all ways.

Fish can survive in a lot of conditions that are not right for them - but as a responsible aquarist the goal should be to have those fish thrive. There is a certain point of pride in knowing you have managed to create and maintain *the* tank your fish need in which to be at their best.