Substrate for Corys

[Dan89]

Hey guys, I should decide what kind of substrate put above my fertilized substrate Dennerle Deponitmix. I was thinking about having Corys in my tank, so I think that sand or fine gravel should be ideal.

Actually I'm quite worried about sand (although it would be the best for corys) because of its hard mainentenace but, most important, because of the risk of creating anaerobic zones.

I would chose the third substrate from the left in the photo attached. The producer labels it as 0,7-1,2mm gravel. Would it be fine for Corys? Is it big enough to avoid risk of anaerobic zones?

 

[fishorama]

Well, from what I can tell, any of those except the far right 1 would be fine. That 1 is likely to compact & may have problems if it's very deep. Sand (except for very fine) is not really difficult but needs different cleaning techniques. A swirling action of gravel vac over the surface is often best. The larger sands/gravel may be able to withstand deeper vacuuming without getting sucked out. How deep will need experimenting & practice.

Good luck! I like the color of the other 3 too.

 

[OrionGirl]

The cories will root through and help with that as well, as will rooted plants and MTS snails. Keep in mind that more than the size, the texture is important. You want smooth stones, not ones that have lots of very sharp edges. Larger stones that are smooth will be much better than smaller stuff that's sharp.

 

[tanker]

I think the second from the right would be OK. If you have Dennerle Deponitmix on the bottom, then the fine sand will eventually go to the bottom anyway.

 

[FreshyFresh]

Agreed. Nice soft, fine substrates mimics a corys natural environment I'd think. Their barbles grow nice and long if it's not too rough. I've kept corys in with large chunky substrate. They did OK, but their barbles did wear down.

 

[dougall]

Is there a reason you want to cap the substrate?

IMO, it should be fine on its own, and capping it with something that has a smaller grain would just leave it sinking to the bottom and the substrate mixing.

 

[fishorama]

You know, I always come back to the ancient RTR post when it comes to sharp substrate & corys. He did an experiment of sharp crushed glass vs bare bottom (but high mulm & nitrate) tank & cory barbel wear. Guess which was better? Glass shards! I'm a believer! RIP RTR!

 

[Ketso]

I have pool filter sand in my 55. The green cories seem to love it. Haven't noticed any barbel issues at all. YMMV

 

[Award Aquarium]

I use gravel with my cories, not super rough and they are doing well. About 1 year and their barbells look great. They do not root hard into the gravel, so it is definitely not their natural substrate.