20 gallon long and the little guppy that could

lotsofcloth

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Short story and then I'll explain why I'm sharing it:

I have two tanks: a 55 and a 20 high. About 10 days ago, I found one of my oldest guppies dead in the 20. I checked water and the ammonia was off the charts (really: as green as the API ammonia goes). It wasn't clear what happened to cause the spike, but it was pretty clear why the fish died. The levels were so high that I moved the remaining fish: 6 skirt tetra and 2 baby guppies - to the other tank. Problem was that there were supposed to be 3 baby guppies - one was there that morning but was gone when I went to move them. I searched everywhere and finally concluded that I must have sucked it up with the Python when doing a water change after seeing the spike. I felt terrible.

After a fair amount of thought and a lucky sale at my local pet store, I decided to exchange the 20H for a 20L. The fish I'd moved to the 55 are happy there so I planned to start fresh with the 20L. I got that tank yesterday. I drained the 20H last night and set it aside. This morning, I put in brand new substrate into the new tank, moved the heater and filter from the old tank, and moved the one plant and the decorations and filled it with water.

And then did a total double take because 10 days after the ammonia spike, 10 days after I last fed in the 20H, there was a very tiny baby guppy now swimming in the 20L.

So I'm calling him my miracle fish. I have no idea how he survived for 10 days or, honestly, WHERE he survived, particularly since I drained the 20H last night and it sat there all night (castle decoration, gravel, one plant, but not water).

The 20L should cycle pretty instantly because I moved the filter over (along with ceramic media and sponge). So I am trying to decide what to stock this 20L with... but it has to include the miracle guppy, because right now I'd like him to be able to have the happiest life he can. Clearly he's a survivor.

I plan to put 5-6 Cories in the 20L, but I'd also like schooling fish, but again, only things that absolutely will leave the guppy alone. Should I get more guppies to keep him company? Other ideas?

Parameters:
-soft water
-PH on the low side (usually around 7)
-avoiding Gouramis and Harlequin Rasboras and cherry barbs (because they're already in my 55)
-zero desire to breed anything
-Happy to add more plants if someone can talk me through how to grow plants in sand (or how to augment the sand with substrate that is plant-friendly without disturbing the guppy, who is near-impossible to catch), what to plant, etc.

Thanks for any ideas.
 

Salty&Onion

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I'm pretty sure that the dead fish has caused the ammonia spike and I suppose that the cause of the guppy's death is the soft, acidic water as guppies aren't soft water fish. They need water hardness of 250ppm and over, in soft water they aren't getting all the minerals they need from this water.

I would not get any hard water fish like guppies, mollies, swordtails and platies. I would not even get corydoras as they need a pH of 7.0-8.0.
I would recommend you to get some kind of tetras and maybe some otocinclus.

Also, what are your water parameters (GH, KH and exact pH?)? What are your ammonia, nitrite and nitrate levels? Exact numbers are needed.
 
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lotsofcloth

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The guppy that died had been in that tank for 2 years - so not sure if it was the water. I don't know if the spike happened just after he died or before. I'd done a water change the day prior and parameters were normal, but I also rinsed the filter in used tank water - which I'd done before - and I scraped algae off the side of the tank - I'm not sure what happened. The ammonia was back to normal after 2 days (e.g. 0).

I'm eating my words a bit because I just tested the water after reading your post, and the PH is 7.6 - higher than in the past. The local water quality report lists the normal range for our reporting area at 7.3-7.6 (it used to be closer to 7).

I don't have a GH or KH kit (have ordered them) but the city water report from May (for the past year) lists GH as 30mg/L with a range of 23-37ppm and the alkalinity at 14.6-18.1ppm. We are on city water so it should be fairly accurate.

I'm not ready to add fish to this tank yet but I can give you the parameters of the 55G and the 20 I had before I emptied it:
0 ammonia
0 nitrite
5 nitrate (I just set this tank up this morning with the re-used media; I expect this number to rise. Typical for my tanks is about 40)
 

Salty&Onion

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From what I understand is that your water is too soft for livebearing fish I'm afraid. It doesn't really matter if the guppy was living in your tank for 2 years, they can and they do live longer, but when in hard water.
I'm pretty sure that the dead fish has caused the ammonia spike and I suppose that the cause of the guppy's death is the soft, acidic water as guppies aren't soft water fish. They need water hardness of 250ppm and over, in soft water they aren't getting all the minerals they need from this water.
 
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lotsofcloth

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I'd far prefer to learn that now than to repeat the mistake. So maybe a school of neons or cardinal tetras? Would Corydoras do okay with the PH of 7.6? Other options that would live well with tetras and that thrive in soft water? The tank is really too short for angels.
 

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20 gallon long is a nice size tank for many small fish. I keep both hard water and soft water fish (in separate tanks) Neon tetras or cardinal tetras are good looking and would do well.' glow light or ember tetras would fit in nicely. Your right angelfish would not work, I had a mated pair in a 55 gallon and would not go any smaller. Enjoyed your story. I had a loach that hid on me in a cichild tank for years. (I thought he was dead) I found him alive and well when I was cleaning out the gravel in the tank and changing it over.
 
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I nEEd mEnTAl HeLP

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I know someone whos guppies survived like 10 ppm ammonia; the API test tube was very very very dark. I also know someone who had a similar experience, they emptied a tank, refilled it, added 2 ppm ammonia and later found a guppy fry.
Yeah fish are mysterious sometimes.
 

LostBear

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Short story and then I'll explain why I'm sharing it:

I have two tanks: a 55 and a 20 high. About 10 days ago, I found one of my oldest guppies dead in the 20. I checked water and the ammonia was off the charts (really: as green as the API ammonia goes). It wasn't clear what happened to cause the spike, but it was pretty clear why the fish died. The levels were so high that I moved the remaining fish: 6 skirt tetra and 2 baby guppies - to the other tank. Problem was that there were supposed to be 3 baby guppies - one was there that morning but was gone when I went to move them. I searched everywhere and finally concluded that I must have sucked it up with the Python when doing a water change after seeing the spike. I felt terrible.

After a fair amount of thought and a lucky sale at my local pet store, I decided to exchange the 20H for a 20L. The fish I'd moved to the 55 are happy there so I planned to start fresh with the 20L. I got that tank yesterday. I drained the 20H last night and set it aside. This morning, I put in brand new substrate into the new tank, moved the heater and filter from the old tank, and moved the one plant and the decorations and filled it with water.

And then did a total double take because 10 days after the ammonia spike, 10 days after I last fed in the 20H, there was a very tiny baby guppy now swimming in the 20L.

So I'm calling him my miracle fish. I have no idea how he survived for 10 days or, honestly, WHERE he survived, particularly since I drained the 20H last night and it sat there all night (castle decoration, gravel, one plant, but not water).

The 20L should cycle pretty instantly because I moved the filter over (along with ceramic media and sponge). So I am trying to decide what to stock this 20L with... but it has to include the miracle guppy, because right now I'd like him to be able to have the happiest life he can. Clearly he's a survivor.

I plan to put 5-6 Cories in the 20L, but I'd also like schooling fish, but again, only things that absolutely will leave the guppy alone. Should I get more guppies to keep him company? Other ideas?

Parameters:
-soft water
-PH on the low side (usually around 7)
-avoiding Gouramis and Harlequin Rasboras and cherry barbs (because they're already in my 55)
-zero desire to breed anything
-Happy to add more plants if someone can talk me through how to grow plants in sand (or how to augment the sand with substrate that is plant-friendly without disturbing the guppy, who is near-impossible to catch), what to plant, etc.

Thanks for any ideas.
Very sad about your guppy death - but how wonderful that one little fry managed to survive so long in such adverse conditions.
 
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lotsofcloth

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Very sad about your guppy death - but how wonderful that one little fry managed to survive so long in such adverse conditions.
Gives me hope he'll hang around for a while :)

Anyone have any advice on the best set-up for neon or cardinal tetras in a 20L? How many, what kinds of plants, what's the best substrate or fertilizer? It already has an inch of white aquarium sand in it.
 

Retired Viking

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In my 55 gallon I have gravel, plenty of ferns and places for them to hide and floating plants like anacharis. Most tetras come from South American jungle streams and rivers so they like shade. They like darker substrate.
 

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lotsofcloth

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In my 55 gallon I have gravel, plenty of ferns and places for them to hide and floating plants like anacharis. Most tetras come from South American jungle streams and rivers so they like shade. They like darker substrate.
I put in sand for the Cories; now I'm wondering if I should layer some Seachem soil-type substrate over the sand? Can you do that once there's already water in the tank?
 

Retired Viking

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I would not put soil over sand or even have soil. It wears out in a year or two and then you have to replace it. Makes for a mess. Most plants like ferns and floating plants get what they need from the water and waste from the fish. The plants that use roots to get what they need you can use root tabs for. Much easier IMO
 
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lotsofcloth

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I would not put soil over sand or even have soil. It wears out in a year or two and then you have to replace it. Makes for a mess. Most plants like ferns and floating plants get what they need from the water and waste from the fish. The plants that use roots to get what they need you can use root tabs for. Much easier IMO
Thank you. I'm new to using sand with plants.
 

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I would not put soil over sand or even have soil. It wears out in a year or two and then you have to replace it. Makes for a mess. Most plants like ferns and floating plants get what they need from the water and waste from the fish. The plants that use roots to get what they need you can use root tabs for. Much easier IMO
It can also leech ammonia
 

Retired Viking

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For tetras you should plan on at least 6 of each type but the more the better since they are shoaling fish and need others of their kind. With a 20 long I would go with just one or two shoals. I have 4 shoals neon, ember, glow light and red eye tetra in my 55 gallon tank. My biggest shoal is my glow light tetra (14)
 

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