Would this be too much for a 20 gallon tank?

OliveFish05

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Hi. We bought a used tank yesterday. We got there and the seller asked if we wanted the 6 fish he had left, which are 3 albino Cories, 2 glow light tetras, and a lemon tetra. I told my mom I wouldn’t mind taking the albino Cories, and she told the guy we wanted the fish. All of them. So now I have the fish. Obviously they’re gonna need bigger schools. They’re lovely fish and now I love them, so I’m gonna them bigger schools. I am just worried that doing that will overstock my tank. I have a 20 gallon that measures 30x12x12. It is densely planted with fast growing plants, duckweed, frogbit, salvinia, water Sprite, hornwort to name a few and has a sponge filter running, and an Aquaclear 50 I could run too.

Ultimately the stock would be
10 Pygmy Cories
8 albino cories
8 lemon tetras
8 neon tetras
8 glow light tetras
1 BN pleco

I am pretty sure I know the answer...
I am able to simply take the fish to my LFS and surrender them if that’s the best option.

I have a 10 gallon quarantine tank by the way.
 
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Hi. We bought a used tank yesterday. We got there and the seller asked if we wanted the 6 fish he had left, which are 3 albino Cories, 2 glow light tetras, and a lemon tetra. I told my mom I wouldn’t mind taking the albino Cories, and she told the guy we wanted the fish. All of them. So now I have the fish. Obviously they’re gonna need bigger schools. They’re lovely fish and now I love them, so I’m gonna them bigger schools. I am just worried that doing that will overstock my tank. I have a 20 gallon that measures 30x12x12. It is densely planted with fast growing plants, duckweed, frogbit, salvinia, water Sprite, hornwort to name a few and has a sponge filter running, and an Aquaclear 50 I could run too.

Ultimately the stock would be
10 Pygmy Cories
8 albino cories
8 lemon tetras
8 neon tetras
8 glow light tetras
1 BN pleco

I am pretty sure I know the answer...
I am able to simply take the fish to my LFS and surrender them if that’s the best option.

I have a 10 gallon quarantine tank by the way
ooof thats a lot of fish. I think that that's a bit too many fish for that size. Maybe you could just keep one or two of the schooling fish species and expand on that?
 
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ooof thats a lot of fish. I think that that's a bit too many fish for that size. Maybe you could just keep one or two of the schooling fish species and expand on that?
*sigh* that’s what I was thinking. I just hate to take them to the LFS... but if it’s what’s best then it must be done.
 
Nix the lemons, for sure...they get too large, and are too boisterous for a tank that size

That's too many bottom dwellers for a 20L, as well
 
Yes I think you do - by my count that's 43 fish!
That’s why I asked:lol: I will have to take the “rescues“ to the lfs...

I’m thinking that even keeping the albino Cories will be too much for the bottom of the tank unfortunately. I think I’ll just take them all to the LFS, I don’t care for the look of the glow lights.
 
Nix the lemons, for sure...they get too large, and are too boisterous for a tank that size

That's too many bottom dwellers for a 20L, as well
Ok, thanks. That was what I was thinking, but just wanted confirmation.
 
That’s why I asked:lol: I will have to take the “rescues“ to the lfs...

I’m thinking that even keeping the albino Cories will be too much for the bottom of the tank unfortunately. I think I’ll just take them all to the LFS, I don’t care for the look of the glow lights.
Good plan

When glolights are healthy, and in a decent sized shoal, they are a spectacular looking little fish....IMO, anyway...one of my faves
 
Good plan

When glolights are healthy, and in a decent sized shoal, they are a spectacular looking little fish....IMO, anyway...one of my faves
My two “rescues“ probably are stressed, come to think of it.
 
The issue here is a very common one...it is not so much the numbers of fish in terms of bioload, it is the number of species that restricts the numbers needed for the species individually. A group of ten of just about any tetra species will without question be better off than a smaller group. This even affects their latency to feed, so for the fish the numbers are crucial.

The Lemon Tetra are too active for this small a tank, as noted. Which is a shame (all else being equal, which obviously it is not) because this is the only species listed that will inhabit the upper half of the tank. All the rest are lower half residents. A group of 10-12 Lemon Tetras in a 30-inch/75cm long tank is minimum for this species to provide the better environment.

Corydoras...I never recommend combining the "dwarf" species like C. pygmaeus with larger sized species. The pygmies tend to get "lost." A group of 12+ pygmies would fare much better than a group of 8. This cory will swim at all levels; mine are often at the surface, browsing floating plant root masses, mid-tank on any plant leaves or wood, and on the sand. They spend less time on the sand than elsewhere.
 
Thank you everyone for your help! I took them to the LFS and got nearly $10 store credit. The glow lights had some issues with their spines, so they didn’t give store credit for that, but they put them in one of their planted tanks and let them live out their days there
 
In time, I have learned the moment I ask myself if my plans would overstock, the question itself tells me I already know better...

This is murder to stick to, but I calculate what a tank can hold, then cut that stocking in half. That's why I have multiple tanks.
 
Hi. We bought a used tank yesterday. We got there and the seller asked if we wanted the 6 fish he had left, which are 3 albino Cories, 2 glow light tetras, and a lemon tetra. I told my mom I wouldn’t mind taking the albino Cories, and she told the guy we wanted the fish. All of them. So now I have the fish. Obviously they’re gonna need bigger schools. They’re lovely fish and now I love them, so I’m gonna them bigger schools. I am just worried that doing that will overstock my tank. I have a 20 gallon that measures 30x12x12. It is densely planted with fast growing plants, duckweed, frogbit, salvinia, water Sprite, hornwort to name a few and has a sponge filter running, and an Aquaclear 50 I could run too.

Ultimately the stock would be
10 Pygmy Cories
8 albino cories
8 lemon tetras
8 neon tetras
8 glow light tetras
1 BN pleco

I am pretty sure I know the answer...
I am able to simply take the fish to my LFS and surrender them if that’s the best option.

I have a 10 gallon quarantine tank by the way.
Out of 3 glow light tetras I got for my tank (32.5 gallons) in 10/20, only one is still alive. The big red one got an internal growth that swelled and broke through the skin as a bloody mess, the second yellow one developed a swim bladder problem that got progressively worse over 6 months. I had to send both to fish heaven. The remaining green one looks great. The glow fish are highly inbred and I would not recommend buying them. One of my younger fish keeping friends had some breed by mistake when they were quarantined after purchase in a breeding net enclosure, and all of the offspring had genetic defects. They may look cool, but there are plenty of better options for pretty fish. Also 2 regular cories and/or 6 pygmies would be the max for your size tank.
 

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