Sand Vs Gravel? Yes, this conversation again. Lol

I don't think sand is better or gravel is better they each are good in their own setups but for the most part sand is just my choice and it seems like the "best" to use
 
Have you seen Corydoras filter feeding as you put it.

This is the way they feed, all species in the Corydoradinae family (Aspidoras, Corydoras and Scleromystax species).

Ok, Now go and look up the definition of filter feeding fish and mammals. What is filter feeding? I say that Corydoras does not fit into that category.
Really, you believe they are that clever?


There is no written law on how one defines this or most other methods/terms that we use in the hobby. The method the Corydoradinae use is certainly filter feeding; they take in a mouthful of substrate and filter out the food items if any, and expel the substrate via the gills. All species live in habitats where the primary substrate is sand, mulm, mud or dried decomposing leaves, either singly or mixed. A very few species occur in a habitat that also includes rock or gravel as part of the substrate. There is no reason to assume these fish would not naturally feed on an insect or insect larvae or crustacean they come across on such a substrate. However, there is clear documented evidence of the fishes' preference, to cite just one recent example:

Scleromystax reisi was found mainly in very small (0.5-2 m wide) and shallow streams (30-60 cm depth), with slow current water and surrounded by relatively preserved riparian vegetation. The bottom was sandy, sometimes covered with a thin layer of mud or fallen leaves. Although there were rocky bottom stretches in the same creeks, the species was never found there [my emphasis]. The streams may have a small amount of submerged vegetation.​
Marcelo R. Britto, Clayton K. Fukakusa and Luiz R. Malabarba (2016), “New Species of Scleromystax Gunther 1864 (Siluriformes: Callichthyidae) - extending the meridional distribution of genera endemic to the Atlantic Forest,” Neotropical Ichthyology 14 (3)​

"The first thing to remember with this group of fishes is that they are primarily filter feeders. They do not have cutting or crushing teeth like some of the predatory Catfish, nor do the have rasping teeth like the grazing Loricariid Catfish, these fish will sift the substrate, which in the majority of cases is sand. In some areas the sand found can be fairly course, and grains could be as large as one millimetre, or as fine as caster sugar, the one thing that will be common is that the grains will be smooth and not sharp and gritty like quarried sand as use in the building industry. Over many years I have spent many hours watching, and filming Cory’s feeding, in some cases it is quite comical, especially with the larger straight (Lineage 8) and curved (Lineage 1) snouted species who tend to bury the deepest, Some almost completely burying themselves when they dive right in searching out the food they sense is there. I have taken video clips of the feeding actions of several species from different lineages. And all, even the smallest species will mouth the sand." (Ian Fuller)​

"Lots of varying parameters can be seen/measured it the habitats where Corydoradinae catfishes are found. I know the exact area where the guys from Aquarium coop saw Corydoras over a gravel/pebble area. These areas are usually where steep fast water streams enter larger streams and or rivers. The natural habitat of Corydoras weitzmani is such an area, in the Rio Araza system at around 850 meters. Aquarium coop staff visited this and and many other locations in SE Peru through my company Go Wild Peru, and they never found Corys over just gravel." [my emphasis] (Ian Fuller)​

As for being clever...this method of feeding is programmed into the genetic data of the species. They do not learn such things, they are born with the instinctive knowledge. Responsible fish keepers will ensure that any Corydoradinae fish have soft sand (no one want mud or mulm); anything less is inhumane because it is deliberately denying the fish something they fully expect.

My ending comment: What is being stated above is scientific evidence that is irrefutable--in other words, it is fact, period. One either accepts it or one rejects it, but there is no agreement or disagreement when it comes to fact. What refutes science is further scientific investigation and empirical data, not opinions, beliefs or the half-baked nonsense one finds on much of YouTube.
 
Have you seen Corydoras filter feeding as you put it.

This is the way they feed, all species in the Corydoradinae family (Aspidoras, Corydoras and Scleromystax species).

Ok, Now go and look up the definition of filter feeding fish and mammals. What is filter feeding? I say that Corydoras does not fit into that category.
Really, you believe they are that clever?


There is no written law on how one defines this or most other methods/terms that we use in the hobby. The method the Corydoradinae use is certainly filter feeding; they take in a mouthful of substrate and filter out the food items if any, and expel the substrate via the gills. All species live in habitats where the primary substrate is sand, mulm, mud or dried decomposing leaves, either singly or mixed. A very few species occur in a habitat that also includes rock or gravel as part of the substrate. There is no reason to assume these fish would not naturally feed on an insect or insect larvae or crustacean they come across on such a substrate. However, there is clear documented evidence of the fishes' preference, to cite just one recent example:

Scleromystax reisi was found mainly in very small (0.5-2 m wide) and shallow streams (30-60 cm depth), with slow current water and surrounded by relatively preserved riparian vegetation. The bottom was sandy, sometimes covered with a thin layer of mud or fallen leaves. Although there were rocky bottom stretches in the same creeks, the species was never found there [my emphasis]. The streams may have a small amount of submerged vegetation.​
Marcelo R. Britto, Clayton K. Fukakusa and Luiz R. Malabarba (2016), “New Species of Scleromystax Gunther 1864 (Siluriformes: Callichthyidae) - extending the meridional distribution of genera endemic to the Atlantic Forest,” Neotropical Ichthyology 14 (3)​

"The first thing to remember with this group of fishes is that they are primarily filter feeders. They do not have cutting or crushing teeth like some of the predatory Catfish, nor do the have rasping teeth like the grazing Loricariid Catfish, these fish will sift the substrate, which in the majority of cases is sand. In some areas the sand found can be fairly course, and grains could be as large as one millimetre, or as fine as caster sugar, the one thing that will be common is that the grains will be smooth and not sharp and gritty like quarried sand as use in the building industry. Over many years I have spent many hours watching, and filming Cory’s feeding, in some cases it is quite comical, especially with the larger straight (Lineage 8) and curved (Lineage 1) snouted species who tend to bury the deepest, Some almost completely burying themselves when they dive right in searching out the food they sense is there. I have taken video clips of the feeding actions of several species from different lineages. And all, even the smallest species will mouth the sand." (Ian Fuller)​

"Lots of varying parameters can be seen/measured it the habitats where Corydoradinae catfishes are found. I know the exact area where the guys from Aquarium coop saw Corydoras over a gravel/pebble area. These areas are usually where steep fast water streams enter larger streams and or rivers. The natural habitat of Corydoras weitzmani is such an area, in the Rio Araza system at around 850 meters. Aquarium coop staff visited this and and many other locations in SE Peru through my company Go Wild Peru, and they never found Corys over just gravel." [my emphasis] (Ian Fuller)​

As for being clever...this method of feeding is programmed into the genetic data of the species. They do not learn such things, they are born with the instinctive knowledge. Responsible fish keepers will ensure that any Corydoradinae fish have soft sand (no one want mud or mulm); anything less is inhumane because it is deliberately denying the fish something they fully expect.

My ending comment: What is being stated above is scientific evidence that is irrefutable--in other words, it is fact, period. One either accepts it or one rejects it, but there is no agreement or disagreement when it comes to fact. What refutes science is further scientific investigation and empirical data, not opinions, beliefs or the half-baked nonsense one finds on much of YouTube.
Thank you for this @Byron!
Really appreciated and very informative!
 
Have you seen Corydoras filter feeding as you put it.

This is the way they feed, all species in the Corydoradinae family (Aspidoras, Corydoras and Scleromystax species).

Ok, Now go and look up the definition of filter feeding fish and mammals. What is filter feeding? I say that Corydoras does not fit into that category.
Really, you believe they are that clever?


There is no written law on how one defines this or most other methods/terms that we use in the hobby. The method the Corydoradinae use is certainly filter feeding; they take in a mouthful of substrate and filter out the food items if any, and expel the substrate via the gills. All species live in habitats where the primary substrate is sand, mulm, mud or dried decomposing leaves, either singly or mixed. A very few species occur in a habitat that also includes rock or gravel as part of the substrate. There is no reason to assume these fish would not naturally feed on an insect or insect larvae or crustacean they come across on such a substrate. However, there is clear documented evidence of the fishes' preference, to cite just one recent example:

Scleromystax reisi was found mainly in very small (0.5-2 m wide) and shallow streams (30-60 cm depth), with slow current water and surrounded by relatively preserved riparian vegetation. The bottom was sandy, sometimes covered with a thin layer of mud or fallen leaves. Although there were rocky bottom stretches in the same creeks, the species was never found there [my emphasis]. The streams may have a small amount of submerged vegetation.​
Marcelo R. Britto, Clayton K. Fukakusa and Luiz R. Malabarba (2016), “New Species of Scleromystax Gunther 1864 (Siluriformes: Callichthyidae) - extending the meridional distribution of genera endemic to the Atlantic Forest,” Neotropical Ichthyology 14 (3)​

"The first thing to remember with this group of fishes is that they are primarily filter feeders. They do not have cutting or crushing teeth like some of the predatory Catfish, nor do the have rasping teeth like the grazing Loricariid Catfish, these fish will sift the substrate, which in the majority of cases is sand. In some areas the sand found can be fairly course, and grains could be as large as one millimetre, or as fine as caster sugar, the one thing that will be common is that the grains will be smooth and not sharp and gritty like quarried sand as use in the building industry. Over many years I have spent many hours watching, and filming Cory’s feeding, in some cases it is quite comical, especially with the larger straight (Lineage 8) and curved (Lineage 1) snouted species who tend to bury the deepest, Some almost completely burying themselves when they dive right in searching out the food they sense is there. I have taken video clips of the feeding actions of several species from different lineages. And all, even the smallest species will mouth the sand." (Ian Fuller)​

"Lots of varying parameters can be seen/measured it the habitats where Corydoradinae catfishes are found. I know the exact area where the guys from Aquarium coop saw Corydoras over a gravel/pebble area. These areas are usually where steep fast water streams enter larger streams and or rivers. The natural habitat of Corydoras weitzmani is such an area, in the Rio Araza system at around 850 meters. Aquarium coop staff visited this and and many other locations in SE Peru through my company Go Wild Peru, and they never found Corys over just gravel." [my emphasis] (Ian Fuller)​

As for being clever...this method of feeding is programmed into the genetic data of the species. They do not learn such things, they are born with the instinctive knowledge. Responsible fish keepers will ensure that any Corydoradinae fish have soft sand (no one want mud or mulm); anything less is inhumane because it is deliberately denying the fish something they fully expect.

My ending comment: What is being stated above is scientific evidence that is irrefutable--in other words, it is fact, period. One either accepts it or one rejects it, but there is no agreement or disagreement when it comes to fact. What refutes science is further scientific investigation and empirical data, not opinions, beliefs or the half-baked nonsense one finds on much of YouTube.
I think it is time you and the scientists that have done this work go and update Wikipedia, Corydoras.
 
When it comes to fact and science, we cannot rely on Wikipedia or any similar sites. I have used Wikipedia to find the references on issues, but not for actual data. I've no idea who writes their stuff, so I would not even read it.
 
When it comes to fact and science, we cannot rely on Wikipedia or any similar sites. I have used Wikipedia to find the references on issues, but not for actual data. I've no idea who writes their stuff, so I would not even read it.
Random people. Literally. Anyone can edit it 🤣
 
The main tank is also a 5g. Looong story. But it is what it is for right now.
Again. We're new(ish). Since last December. Made every mistake in the book. Plus more.
We are currently investigating upgrading to a 20g tank. But I'm not jumping right in so to speak. Before I do jack or squat, I want to understand what products to buy, filters, lighting, etc., as these will be important. In this hobby, it seems like one overlooked or minor mistake or misjudgment can completely ruin everything.
Same here. One of these days, I'm going to start a thread of all the rookie mistakes I've made so far. I'm still learning a lot. I've found this forum to be very helpful.
 
When it comes to fact and science, we cannot rely on Wikipedia or any similar sites. I have used Wikipedia to find the references on issues, but not for actual data. I've no idea who writes their stuff, so I would not even read it.
The said thing is that hard science is actually one of the more reliable topics on Wikipedia. Which just goes to show you how unreliable Wikipedia is as a whole.
 
When it comes to fact and science, we cannot rely on Wikipedia or any similar sites. I have used Wikipedia to find the references on issues, but not for actual data. I've no idea who writes their stuff, so I would not even read it.
Well, the least Ian Fuller and yourself can do is make sure that the stuff written about Corydoras Is 100% factual, so it helps to remove all the other stuff written about Corydoras. It is most important that the information about filter feeding, and sand is written on this site.
 
Well, the least Ian Fuller and yourself can do is make sure that the stuff written about Corydoras Is 100% factual, so it helps to remove all the other stuff written about Corydoras. It is most important that the information about filter feeding, and sand is written on this site.

I certainly agree that all of us have the responsibility to be factual when offering advice on fish, but who has time to correct the multitude of misleading and some downright false information on the internet? And, many believe some of these misleading sites to be accurate, and continually having to point out the truth does get tiresome. Some people do not want the truth anyway, so one will have on-going discussions (at best) or blatant nasty argument (too often) with no achievement.

There are sites of reliable information, and many members here do try to steer others, especially beginners, to these sources.

Another issue, I am not going to put my name on data I might post to Wikipedia if there is the probability that some half-wit will change it. In other words, I have no control over it. When I was on another then-good forum some 12 years ago, I was given responsibility for the new Knowledge section. I wrote more than 200 (208 I think) freshwater fish species profiles and 41 freshwater plant species profiles. The site changed ownership, and I along with others like AbbeysDad, resigned. I do not direct others to those profiles now because (a) it is another fish forum, and (b) I have no control over changes, and I cannot guarantee the data. I use my own drafts which are accurate.
 
I certainly agree that all of us have the responsibility to be factual when offering advice on fish, but who has time to correct the multitude of misleading and some downright false information on the internet? And, many believe some of these misleading sites to be accurate, and continually having to point out the truth does get tiresome. Some people do not want the truth anyway, so one will have on-going discussions (at best) or blatant nasty argument (too often) with no achievement.

There are sites of reliable information, and many members here do try to steer others, especially beginners, to these sources.

Another issue, I am not going to put my name on data I might post to Wikipedia if there is the probability that some half-wit will change it. In other words, I have no control over it. When I was on another then-good forum some 12 years ago, I was given responsibility for the new Knowledge section. I wrote more than 200 (208 I think) freshwater fish species profiles and 41 freshwater plant species profiles. The site changed ownership, and I along with others like AbbeysDad, resigned. I do not direct others to those profiles now because (a) it is another fish forum, and (b) I have no control over changes, and I cannot guarantee the data. I use my own drafts which are accurate.
That is a pity you refuse to correct misinformation on the internet. I thought you would be one person who would want to see this sort of thing corrected.
 
That is a pity you refuse to correct misinformation on the internet. I thought you would be one person who would want to see this sort of thing corrected.

With all the misinformation spread across the internet, no single person could possibly correct it in a whole lifetime. And what is the point of my correcting one Wikipedia article, when there are hundreds, probably thousands, of inaccurate fish sites available. It is of more value to point out where the correct information can be found.
 
I screwed up by not knowing better. I put in small gravel and later got cories. They seem to do OK on the gravel; they are fat and happy.
 

Most reactions

Back
Top