small rocks in play sand harmful?

[Ophelia]

Hi everyone, first time poster here (but long time lurker) and very much enjoying the community.

I recently discovered the joys of corys, which have quickly become a family favorite. I did my research before hand, and decided to switch my substrate to sand, considering all of the benefits it provides. I purchased play sand, making sure to feel it before hand to make sure it was fine enough and not too rough. Through the cleaning process, I didn't noticed the tiny rocks that were mixed in with the sand, but only realized after the water cleared and everything settled.

For the most part the sand is all fine grain, and corys are still happily sifting through it. But I'm worried some of the tiny rocks might injure their barbels. Will they be okay or should i look for a way to remove them? If so, do you have any tips on the easiest way to filter them out?

Here's a photo of what it looks like:

Thanks for any advice you can provide!

[Richard B]

It looks fine to me, & more natural like that

[bbetta]

Looks good to me too!

[jp11biod]

IMO the sand with a little gravel is fine and not a problem. I do think your sand is too deep. For cories to keep it clean, I think the experts recommend no more than 1/2 an inch

[Ophelia]

Thanks everyone! Glad to hear I will *not* have to sift through all that sand.

The sand is about an inch deep, since i have some plants in the tank. I'll be making sure to comb through it during weekly water changes, and I'm considering getting some trumpet snails to help air it out as well.

Once I have a bigger tank, I'll definitely have some thinner areas where they can dig all the way through to the bottom

[bbetta]

I don't think 1 inch of sand will be an issue. Many of as have way more because of the plants. Also , be careful with your snail population.

[dw1305]

Hi all,
For me the only problem is that over time you'll find all the small rocks migrate to the top, above the sand. It is a process called "granular convection".

cheers Darrel

[Ophelia]

Thanks all!

I've removed the bigger ones by hand but I think I may sift through the top layer to try to remove what I can during the next cleaning/water change.

[racoll]

I've removed the bigger ones by hand but I think I may sift through the top layer to try to remove what I can during the next cleaning/water change.

Don't waste your time. Your substrate is perfect.

I think that damaging substrates are the ones with large and sharp pieces of gravel that cannot move when the Corydoras forage between them, hence they degrade the barbels. In mixed grade substrates like yours, the small pieces can easily be pushed aside during foraging, so they will cause no problems even if they appear "sharp".

[Ophelia]

That's reassuring, thank you racoll! They seem to be very happy, and they do push around the rocks. Will leave things as is