River sand - cories don't seem to like sand?

[squid]

Hi,

I just added some river sand to a portion of my cory tank, but i noticed that they don't seem to like to play in the sand or stay in the sand? thye seem to stay in the barebuttom part of my tank.

now thinking if i should just remove the sand? I sprinkle food near the sand . they will only go there if theres food?

thanks.

[MatsP]

"river sand" can mean a lot of different things.

Is it very light in colour? If so, the cory's may avoid it simply because they prefer the safety of a darker background (bare bottom).

Is it "smooth" - if you rub the sand between your fingers, does it feel fairly sharp or quite smooth?

Other than that, I can't really suggest anything.

--
Mats

[Birger]

Give them some time as well, if they are used to or have grown up in a bare tank it will be foreign to them until they figure it out.

[skaskankerbr]

I doubt you watch your cories all the time. They tend to stay in a safe cave or in a corner of the tank when your watching. However about 1am if you watch them with no lights you will see amazing things. I see my cories dancing across the tank schooling in groups of three. They parade around doing flips, playing with plants, swimming into the bubbles.
I'd say to truely enjoy your corys, watching them at night is the only way.
Also sand is reccomended , but unrealistic. The amazon has sand i am sure , but basically it's mud. However no one wants to keep river mud in their tank.

[Jools]

I doubt you watch your cories all the time. They tend to stay in a safe cave or in a corner of the tank when your watching. However about 1am if you watch them with no lights you will see amazing things. I see my cories dancing across the tank schooling in groups of three. They parade around doing flips, playing with plants, swimming into the bubbles.
I'd say to truely enjoy your corys, watching them at night is the only way.
Also sand is reccomended , but unrealistic. The amazon has sand i am sure , but basically it's mud. However no one wants to keep river mud in their tank.

Actually, I find the corys that I've kept are pretty active and visible during the day if kept optimally. If they're not, then I'd look at why they are not out and about. A good starting point are the addition of floating plants but there could be many reasons why they are timid during the day.

The Amazon isn't basically just mud, all though there is a heck of a lot of it I can't remember every encountering a Corydoras on plain mud flats. There are all sorts of substrates where Corydoras are found. However the point is what species of Cory are we talking about, many are not from the Amazon for starters and they can be found over sand, mud, leaves and even in wood thickets, vegetation or over rocks. Many species are found in several different biotopes which can also seasonally change.

That's just based on having been there, having collected

Corydoras

in 4 countries in South America and around 20 odd years of keeping them for what its worth.

Jools

[skaskankerbr]

then you know more than i do about the soil structure of the amazon. lol i can only read not see. I did read an article saying they liked to bury themselves in mud.
My corys while active in the morning are very scared of people. They tend to be shy and when approached cluster up under or in something. While they do swim around and play during the day i just find they feel safer at night. I have a black light in the back that illuminates the tank from the bottom up.

[andywoolloo]

I agree that it might seem like a strange feeling to them at first, my cories loved sand. I had dark sand. or maybe it is the texture of the sand like Mats says?

and mine stayed out all the time and just did their thing, they didn't care who was by the tank. Maybe it has to do with tank decorating? Mine had lots of hidey areas and driftwood and rock. and plants.

[torbanite]

It may be that the lack of interest is partly because new sand will not yet have much biology going on it?
Once it has been there a while and little bugs & beasties colonize it, the fish may show more interest...

I have three Cory tanks, two have soft sand, the other has 3mm pea gravel. The fish in the sandy tanks dig & sift enthusiastically. They remind me of mini snow-blowers the way they plough along with a stream of sand coming out of their gills.

In the gravel tank, only the bigger females can make much impression on the substrate. When I vacuum it, there is always scrum of hopeful Cory's following the syphon around waiting to pounce on whetever I stir up for them. The only reason I have not converted that tank to sand as well is the worry that I'd upset the cycle & do more harm than good.

I experimented with leaf litter in one tank for a while. The Corys absolutely loved it, but I found it impractical because they'd stir it up, the filter would "eat it" & get blocked. Also, the idea of large amounts of slowly rotting vegetation in a closed system worried me too much.

Martin

[OldMan]

Torbanite, if you are not using an under gravel filter, there is no need to worry about your cycle by changing substrate. Keep in mind that you will need to clean the existing substrate thoroughly before trying to make the change. The problem this addresses is that by stirring the gravel, you will expose lots of mulm in the substrate and you want to minimize the biological impact that could have on your water. So to make the change, first a thorough cleaning of the existing substrate and a thorough cleaning of the new sand. When all is set, remove the existing substrate, easier done with low water levels. Then add in the new substrate and bring the water level back to normal.

[torbanite]

Torbanite, if you are not using an under gravel filter, there is no need to worry about your cycle by changing substrate.

Thanks for the advice OldMan. It isn't an under gravel filter.
I guess I'm just Mr. Hyper-cautious .

If my courage holds, I may have a go at it over the Christmas holidays as I'll have the time to keep an eye on things for the day or two after. There are a couple of other (to my mind) complicating factors, but best I start a separate thread for that rather than hi-jack this one.

thanks,
Martin

[squid]

thanks do i have to clean the sand regularly?
btw here are some pictures of the sand i added, does it look cory safe?









thanks.

[fish fodder]

Looks pretty sharp tbh. could have an issue with their barbels getting damaged. play pit sand i think is the best, cheap and easy to get hold of, and completly safe for aquarium use

[bslindgren]

That looks like volcanic material, which would be very sharp. I use pool filter sand, which is recommended for loaches, and they often feed in a similar manner to cories. My cories (

Corydoras aeneus

and

Corydoras sterbai

) sure seem to like it. They poke around like little piggies in the sand!

[squid]

thanks i will try to remove the sand