A weird situation...

[badpotato39]

So I've had this planted 20 gallon long running for about a month.  Due to reasons I wont get into, I'm now the proud owner of 12 Orange Venezuelan Cory's.  I'm worried about the substrate and stocking levels of the tank.  The substrate is a mix of eco-complete and aqua natural midnight pearl.  Filtration is a dual sponge filter with a Fluval U2.

Questions:

1) Is the substrate going to be ok for these guys?  I plan on keeping them so I want to make sure they aren't going to get injured with it.

 

2) What do my stocking options look like for the rest of the tank?

 

Any help/guidance would be appreciated.

Edited September 1, 2023 by badpotato39
Clarify tank size

[nabokovfan87]

On 8/31/2023 at 7:52 PM, badpotato39 said:

1) Is the substrate going to be ok for these guys?  I plan on keeping them so I want to make sure they aren't going to get injured with it.

Personally, I would replace it.  I can give you some recommendations, you can also just cap it with sand too.  There are a plethora of options.  I would recommend a feeding dish / plate if you don't have a fine substrate for feeding.  It helps them to be able to eat the food in question and access it.

I have heard many say they don't have issues, but I have also seen a lot with damage on the corydoras from eco complete.
 

On 8/31/2023 at 7:52 PM, badpotato39 said:

2) What do my stocking options look like for the rest of the tank?

Pretty much whatever you'd like.   White clouds would be nice.  CPDs, rasbora, small barbs.  (they tend to like the same water parameters and temp as the corydoras)

 

[Odd Duck]

On 8/31/2023 at 9:52 PM, badpotato39 said:

So I've had this planted 20L running for about a month.  Due to reasons I wont get into, I'm now the proud owner of 12 Orange Venezuelan Cory's.  I'm worried about the substrate and stocking levels of the tank.  The substrate is a mix of eco-complete and aqua natural midnight pearl.  Filtration is a dual sponge filter with a Fluval U2.

Questions:

1) Is the substrate going to be ok for these guys?  I plan on keeping them so I want to make sure they aren't going to get injured with it.

 

2) What do my stocking options look like for the rest of the tank?

 

Any help/guidance would be appreciated.

By 20L, do you mean a 20 gallon long or a 20 liter tank?  Because that’s a very big difference.  A 20 G long is fine for 12 cories, but I would personally tend to go very light on other stocking since cories have fairly bulky bodies.  If it’s a 20 liter tank, I don’t think I’d put anything besides the cories in that and it would be a very high bioload at that.  A 5 gallon tank would be very small for full size cories like Venezuelans.  It’s pretty small but not impossible for the mini cories like pygmies.  I’m guessing you’re talking 20 gallon long based on your filter choice.  Just wanted to clarify for an international group.

[badpotato39]

Just to clarify, this is a 20-gallon long tank.

What are some thoughts on moving 6ish of them to a planted 10 gallon with a male betta that is pretty docile?  Substrate is the same.

 

As far as substrate goes, would the fluorite sand be a good option for both plants and cory's?

[nabokovfan87]

On 9/1/2023 at 9:55 AM, badpotato39 said:

would the fluorite sand be a good option for both plants and cory's?

I started with that in my 29 and then my 75G I ended up moving away from it. The flourite is fine as a cap and works just well with corydoras. I use the normal black one. That being said, for plants it's just soft gravel and it's not really something with a high CEC. It might have minerals for the plants in there, but it's not easy for them to access it from what I have experienced.

In the end I used aqua soil as a base, contrasoil specifically, but used the fluorite black as just a cap.

Cost aside, my preference would be medium size contrasoil as the base, fine size as the top and using that as the substrate.

I would be interested if it was heavy enough for the corydoras (which it should be, but is why I have the cap right now).

[Odd Duck]

I’ve gotten away from fluorite anything since they can’t seem to keep magnetic bits out of their substrate.  I don’t think cories are nearly as particular about their substrate as some seem to think.  I’ve had them on all sorts of substrates over the years and the only barbell issues were if they got some bacterial infections and had damage from that.  Most sand is pretty inert unless it’s coral or aragonite sand or other types that tend to raise pH.  Primarily quartz-based sand is a non-issue.  Black blasting sand has been a non-issue for me.  Sand is going to need root tabs or liquid ferts since it has minimal to no nutrients, or course.  IME, plants seem to like the texture of sand for growing.

[badpotato39]

Just an update- 

I ended up simply removing about a 10x6 section of the gravel substrate and replaced it with the super natural fine sand. I’m treating that as essentially a “feeding plate”.  I also did this on a smaller scale for the other 6 that went in the 10 gallon. They all seem to love it. They go crazy shoving their faces into the sand.