Cories for my 20g?

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Aquarium Advice Freak
Jan 22, 2008
Well, my 20g is stabilized now (WOOHOO!) Aside from the very sad loss of one of my female bettas, everyone, including the newly added Otos, is doing extremely well, and the plants look great! The crypt spiralis is alway pearling like mad when I come home from work!

Anyways, now that we're stabilized I was thinking of adding a few more fish to round out the tank. I was originally just going to add back the 2 glowlights i lost when the pH was very low, and perhaps another couple of neons and glowlights, however, the 7 neons and 5 glowlights regularly school together, so I'm thinking of putting something else in there instead. I fell in love with the adorable pygmy cories I put in my 5g that sadly did not make it. Would these be a good option for the tank? Is there a larger cory (easier to find
) that I should look at instead? Or do we think I am too heavily stocked to add a small shoal of any sized cory?

Tank is 20g high, penguin biowheel filter, for stocking see my signature, an d for more tank specifics, click the link

As ever, thanks in advance for the helpful advice I know i'll get!
Thanks! I know where I can get pygmies too, but i'm worried i'll never be able to find them in the jungle of the 20g! hahahaha but i'm wondering whether i have room for a nice school (5-6) of anything larger than the pygmies? I do like the pandas! :)

Oh I saw you have a good amount of fish in there already, so better wait for an expert on that.

I'm just interested in how your plants are doing and what are you using, like ferts, ect.. I have a 15w light over my 10gallon so its a similar light condition.
Well, you can check out my journal thread as listed in my signature for more details, but my plants, somehow, do quite well, despite only .75wpg (if you have 15w over a 10g you actually have double what I have). I dose Flourish Excel and Comprehensive, excel ~twice a week, comprehensive, ~once a week. I've forgotten to dose before though and the plants still do well. I don't know how or why, but they grow like mad in there! :)
Yeah I'm not using ferts but things are growing(slowly). How long do you leave the light on for?

I like your gravel, I plan on taking out some of my blue gravel and adding black gravel or maybe aquasoil to it
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if you have 15w over a 10g you actually have double what I have

The key difference here is the size of the aquariums. A 20 gallon is really the smallest aquarium where the WPG "rule" is at all useful. With smaller aquariums you need more light to reach the various lighting thresholds. So as far as useful light, the two aquariums are probably fairly comparable.
Interesting, I didn't realize that. Thanks!

Also, any more thoughts on cories for my 20g?
Personally I'd still go for the Dwarf Cories if you can get ahold of them. It'll be much easier to get a nice size school of them without pushing the bioload as much. There is such a difference in activity going from say 3 cories to 5-6 cories. They'll much more fun to watch in a good sized school.
Great, thanks! Would you consider pandas or habrosus to be in the dwarf category even though they're a bit larger than the pygmeaus or hastatus?
I just acquired my peppered cories yesterday. They are adorable! I had originally wanted either dwarf or panda, but by lfs (Petsmart) didn't have any and said they rarely get any in. They had the emerald green and the peppered cories. I got three of the peppered and they are in their QT tank right now. They are just so cute and fun to watch. Very active!
Awesome! I enjoyed mine a lot too for the short amount of time i had them. I've decided the 5g is too easy to de-stabilize, at least for now, maybe once the plants grow in quite a bit more, i'll think about SLOWLY adding a few cories back. Hence, i'm looking for ideas for the 20g, but it's already got a fair few fish....I'm thinking habrosus, hastatus, pygmaeus or POSSIBLY pandas. I'm not sure i'd be able to get a large enough school (5-6) to make the pandas happy without way overloading the bioload, unless they're quite young when I get them. So i'll be looking around to find what's available this week :)
I Got My Cories!

And they gave me extra! I asked for 6 but said if that only left 1 or 2 I'd take them, we thought there was only 2 left, ended up being for. So I came home with 10 Corydoras pygmaeus but only charged for 8. I thought that was a pretty good deal! I have enough to try a few in my 5g again if I want to. I'm a little worried about overloading the bioload in there though.

Anyway, they're currently drip-acclimating to the 20g. I think i'll QT them using some water from the 20g, I can't decide if I should just stick them straight into the 20g though. They're from the same batch that I got cories from a few weeks ago, so I imagine they're the heartiest, disease free ones, but that doesn't rule out bringing disease IN to the tank and other fish. So I suppose I just answered my own question :p I'll see how many survive QT (hopefully all!) before deciding whether to try some in my 5g again. It'll probably depend a lot on whether that tank is still stable, and how much the plants have grown in!

Pics of the new additions to come...
Thanks! I'll be sure to post pics when I can get them :)

Here are some pics of the little guys in their QT home. They all look really happy and healthy so I probably won't leave them in there for too too long, but better safe than sorry since i've been too lucky thus far with not getting disease outbreaks by not QTing fish.

Any here are the new additions:

Schooling together:


Resting together: (i'm not sure what setting I had the camera on that this came out so orange, but i thought it was a cool pic anyway)
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