Emerald Green Corydoras

[Pittsford_Pets]

I know this isn't salt, but I lost one of my 5 emerald green corydoras today. They're in my 20g high tank, sand substrate, tons of plants, and some rocks. pH is about 6.8 - 7.2, varies with my test kits (I have 2 sets of ATI so I just do two each week or so). They've been eating well, no aggression in the tank, so it comes as a bit of surprise. Don't worry, it's not an overstocked tank either. I just have a neon dwarf gourami, the 5 (now 4) corydoras, 3 adult platys, and some Platy fry that I've been catching and moving to a 10g grow out. I do weekly water changes with dechlorinated tap water and feed NLS small fish pellets with the occasional flake/frozen food.

Any ideas? Everyone seemed fine and parameters all check out.

 

[Zack K]

Is this a freshwater question? If so I’m not sure how many people can help here. As this is predominately a Saltwater Forum

 

[Pittsford_Pets]

Is this a freshwater question? If so I’m not sure how many people can help here. As this is predominately a Saltwater Forum

Yes, it is. I've had a few people help me out on here with other freshwater questions, and it's also common for people to start with freshwater and move onto saltwater.

 

[Maritimer]

What kind of substrate are they on?

I know cories prefer soft sand over gravel. Your husbandry would seem to be OK, from the info you've given.

~Bruce, one of the ones who moved over from the sweetwater side

 

[Pittsford_Pets]

What kind of substrate are they on?

I know cories prefer soft sand over gravel. Your husbandry would seem to be OK, from the info you've given.

~Bruce, one of the ones who moved over from the sweetwater side

Yep, I have some pretty fine sand. I can't think of the word right now - but their little whiskers are long so I know the substrate is good.

 

[Gareth elliott]

How long has the tank been setup? How long ago did you add the corys?
Were they full size at purchase?
Sometimes the fish can be much older than we think they are.
By chance did you take any pictures of the lost fish or notice any external disease?
In case its a contaminant issue you should be safe doing a 50% wc as freshwater large changes are normal rainy season/dry season. This is actually one of the cues I add to get my corys to breed.

 

[Pittsford_Pets]

How long has the tank been setup? How long ago did you add the corys?
Were they full size at purchase?
Sometimes the fish can be much older than we think they are.
By chance did you take any pictures of the lost fish or notice any external disease?
In case its a contaminant issue you should be safe doing a 50% wc as freshwater large changes are normal rainy season/dry season. This is actually one of the cues I add to get my corys to breed.

The tanks been set up for about a month. Used some cycled filter media as well as sand and rocks, too. I added the corydoras a few weeks ago and they're about an inch and a half to two inches as of right now. The fish looked fine so I was pretty confused... My Thanksgiving break starts tomorrow so I'll strip the tank down (then put everything back) as it needs some trimming and I'll be able to examine each individual fish closer. Would baby corydoras survive in a heavily planted tank with a gourami and platys?

 

[Gareth elliott]

The tanks been set up for about a month. Used some cycled filter media as well as sand and rocks, too. I added the corydoras a few weeks ago and they're about an inch and a half to two inches as of right now. The fish looked fine so I was pretty confused...

Have you gotten a nitrate reading yet? And are both ammonia and nitrite testing 0?

My Thanksgiving break starts tomorrow so I'll strip the tank down (then put everything back) as it needs some trimming and I'll be able to examine each individual fish closer. Would baby corydoras survive in a heavily planted tank with a gourami and platys?

No but corys, at least those ive kept, lay their eggs on the glass and can be carefully removed and hatched in a separate tank. The fry are much smaller than the platy young. For more in depth freshwater help i recommend other forums

 

[eatbreakfast]

Don't strip the tank down, that just destabilizes everything and stresses out the fish.

 

[Pittsford_Pets]

Don't strip the tank down, that just destabilizes everything and stresses out the fish.

By strip the tank down I meant take the plants out so I can better monitor each individual fish. As the tank is heavily planted, I can't see each fish at all times.

Nothing will be removed but plants, keep water (minus the 50%) and filter media.

 

[eatbreakfast]

I would advise to leave the plants in place. Removing them will only further stress the fish.

 

[Fritzhamer]

Very true plus if you started with plants they will be providing most of the biological filtration. Even if you added them later they'll possibly out-compete the biological filtering bacteria. I've run many freshwater tanks over the last two decades without filtration or much circulation, just live plants and no water changes (Natural / Walstad method).

 

[ThunderGoose]

I'm with the large water change and leave the plants camp. Your tank is young. Let it mature, no more new fish for a while. I find it's not unusual to loose fish shortly after arrival (first few weeks). You have no idea how old they are, what conditions they're used to, and the shipping process and new habitat are very stressful.

My green corys have reproduced in my heavily planted tank at a low rate - just the occasional fry survives.

 

[Pittsford_Pets]

I would advise to leave the plants in place. Removing them will only further stress the fish.

I'm keeping most of them, just a bit of a trim.