Absolute disaster! Managed to suffocate my fish!

AngelaBoyceBlackburn

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So, I am absolutely distraught at this but I'm hoping there will be some helpful advice coming my way and not nasty hurtful comments

Set up for my usual weekly water change. I do at least 30% change as I always had semi-high ammonia so been treating with API AmmoLock along with my usual Seachem Prime..

Removed as much waste from the sand as possible, gave the hardscape a but of a swoosh and set them back in place

Then I started with my basins, water jug and chemicals but I stupidly forgot to add them to the basin before transferring the water to the tank and this is where it all went so catastrophic I'm still beating myself up 24hrs later..

Prime was fine, 79l tank so added 1 & 1/2 caps slowly over the water but the AmmoLock... aw my god did I not drop the bottle into the tank and discharge at least 100ml into their home!!

2 seconds later my Cardinals were flooding the surface gasping and slowly dying off! My Betta was doing ok but still coming up for air so I had to start decanting water straight back out basin by basin down to 20% remaining to clear it and just fresh clean dechlorinated tap water (honestly felt like my kitchen tap was on slow flow!) however, 3 out of 18 of my Cardinals survived, my Betta is an amazing little fish and is swimming like nothing ever happened and my 6 nerites seem to be ok as well (I'll be keeping an eye out for their movement or lack thereof)

What's my next moves? Do I keep doing some daily changes until we're back in the safe zone and jow do I know it's safe? I don't want to replace the tetras, having so many in a 70l with the Betta and nerites was a bit of an overstock but my parameters taken this morning seem to be ok (please see my pic)

Any helpful advice would be great, I don't need anyone being nasty or telling me I'm an idiot (I know I made a mistake!) so if you would like to contribute positively, I'd love to hear from you

A x
 

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Best case scenario, products that "lock up" or "detoxify" ammonia are only effective for 24-48 hours, and there is plenty of debate whether they actually work at all.
I would probably do a series of 50% water changes.
Where is the ammonia coming from?
Why can't your filter process it?
 

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Best case scenario, products that "lock up" or "detoxify" ammonia are only effective for 24-48 hours, and there is plenty of debate whether they actually work at all.
I would probably do a series of 50% water changes.
Where is the ammonia coming from?
Why can't your filter process it?
My PH is so low, barely giving a reading so I've added a massive bag of crushed coral to lift it which is whu I'm now getting a more decent reading
Well that's what the guy in the store told me anyways
Before these readings and prior to my disaster my ph was barely 6.0, ammonia was closer to 4, nitrite and nitrite were high as well (but because the ammonia wasn't converting? Is that right)
So I may have inadvertently kick started things
 
Aquarium water conditioners like Seachem Prime and Ammo Lock contain sodium thiosulfate to dechlorinate tap water by reduction of the chlorine to chloride ion. Adding one or the other is likely safe as long as you do not subscribe to the theory "if a little is good, more is better". However, by adding both, you swung the reduction-oxidation potential of the water from the oxidation side (oxygen in the water), to the reduction side in which little or no oxygen is present. Please do not make that mistake again.

An air stone with very fine bubbles will help to aerate the water, drive off carbon dioxide and add oxygen to the tank.
 
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  • #6
Aquarium water conditioners like Seachem Prime and Ammo Lock contain sodium thiosulfate to dechlorinate tap water by reduction of the chlorine to chloride ion. Adding one or the other is likely safe as long as you do not subscribe to the theory "if a little is good, more is better". However, by adding both, you swung the reduction-oxidation potential of the water from the oxidation side (oxygen in the water), to the reduction side in which little or no oxygen is present. Please do not make that mistake again.

An air stone with very fine bubbles will help to aerate the water, drive off carbon dioxide and add oxygen to the tank.
Thanks
Yeah I have the bubble bar turned up as high as possible and the filter on a fast-flow for a bit and done another 30% change yesterday
Got a green killing machine (previous advice on another thread was an absolute god-send!) So I'm no longer tempted to go anywhere near the AmmoLock and it's Seachem Prime alone from here-on in
The remaining tetras are thriving, no gasping at the surface, displaying normal behaviour even if they look a little lonely being so few now but there's no way I'm increasing their number right now
My Betta is a sturdy little trouper, he's the one I'd have been more devastated about if I'd lost him
 

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Mistakes happen, we learn from them. Might be better to measure chemicals to be added over the sink or bucket, Then whatever you drop into the aquarium can only be the right amount. Keep a cup for this use and nothing goes near the tank but the cup with the right stuff.
 
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  • #8
Mistakes happen, we learn from them. Might be better to measure chemicals to be added over the sink or bucket, Then whatever you drop into the aquarium can only be the right amount. Keep a cup for this use and nothing goes near the tank but the cup with the right stuff.
I usually do, that's the thing.. when I'm filling from the tap and a kettle to temp match its all done at the sink however (and not an excuse) but I'd finished a 12hr nightshift 8am that morning and couldn't sleep and by the time it was 10pm I'd been awake for close to 40hrs so my brain disengaged ‍♀️
Believe me, I've learned my lesson
 
Yes…..important…..where is the ammonia you mentioned coming from?
From the pic I see a favorable ammonia reading, but it could be off with my iPad screen.
What is your pH, KH, and GH of both your tank water ..and.. source of fresh new water (tap) water?
Mixing done away from actual tank water is the way to go.

Believe me when I say we all have had our moments of despair after a mistake, equipment malfunction, or mega disease. When it happens, be sad, learn from it, research options, and proceed with corrections to avoid repeating. Don’t beat yourself up over it……doing so will both take the enjoyment of the hobby away and not allow you to learn and grow. I’ve been doing this for decades and still make mistakes and am still learning/picking up new ideas. Lastly……I guarantee that not one of us was born knowing everything no matter how harshly one may respond, but the people here are pretty supportive and understanding overall.
 
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  • #10
Yes…..important…..where is the ammonia you mentioned coming from?
From the pic I see a favorable ammonia reading, but it could be off with my iPad screen.
What is your pH, KH, and GH of both your tank water ..and.. source of fresh new water (tap) water?
Mixing done away from actual tank water is the way to go.

Believe me when I say we all have had our moments of despair after a mistake, equipment malfunction, or mega disease. When it happens, be sad, learn from it, research options, and proceed with corrections to avoid repeating. Don’t beat yourself up over it……doing so will both take the enjoyment of the hobby away and not allow you to learn and grow. I’ve been doing this for decades and still make mistakes and am still learning/picking up new ideas. Lastly……I guarantee that not one of us was born knowing everything no matter how harshly one may respond, but the people here are pretty supportive and understanding overall.
I think it was partly down to the tank being overstocked prior to this.. as well as the betta and 18 Cardinals I had taken out a total of 13 corys, the store took them back when I explained Sapphire's behaviour was becoming reclusive, they were far too energetic and excitable for him with their constant movement - there was no clash or anything they just took over and the happy equilibrium was bust so possibly the amount of waste being produced caused the ammonia to be on the high side then the filter couldn't cope with the volume and just bacterial crash so I picked up some live bacteria to kick-start it as well as the fresh coral so that seemed to work
I don't have a test kit for Kh and Gh so I'll need to pick one up to test the tank and the tap (source) water
 
I'm so sorry this happened. It's awful feeling, for sure. like said above, be sad, give yourself some time.
 

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Yes…..important…..where is the ammonia you mentioned coming from?
From the pic I see a favorable ammonia reading, but it could be off with my iPad screen.
What is your pH, KH, and GH of both your tank water ..and.. source of fresh new water (tap) water?
Mixing done away from actual tank water is the way to go.

Believe me when I say we all have had our moments of despair after a mistake, equipment malfunction, or mega disease. When it happens, be sad, learn from it, research options, and proceed with corrections to avoid repeating. Don’t beat yourself up over it……doing so will both take the enjoyment of the hobby away and not allow you to learn and grow. I’ve been doing this for decades and still make mistakes and am still learning/picking up new ideas. Lastly……I guarantee that not one of us was born knowing everything no matter how harshly one may respond, but the people here are pretty supportive and understanding overall.
Oh, the ammonia is the latest reading and definitely much much better than it was on but I'm keeping an eye on it just incase

The husband (who hates this hobby ) has said the tetras need some more tankmates, I know myself they need 6 minimum for a comfortable shoal so I'm now considering a very very small increase
I'm all about my Sapphire's comfort so there's no way I'm going to increase them by too much
 
Ok so beneficial bacteria development is reduced at a low pH. However at pH of "barely 6" that ammonia should be in the form of ammonium NH⁴ which should be non toxic to fish.
So while you may be able to detect it with your test kit, I'm doubting that's the cause of your fish gasping at the surface and dying.
 
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Ok so beneficial bacteria development is reduced at a low pH. However at pH of "barely 6" that ammonia should be in the form of ammonium NH⁴ which should be non toxic to fish.
So while you may be able to detect it with your test kit, I'm doubting that's the cause of your fish gasping at the surface and dying.
The only thing that went wrong was the AmmoLock bottle being dropped into the water, it was almost instantly after this that they started dying off, not that the ph level was low - it's always been barely detectable hence the crushed coral sand in an attempt to increase this

Yes…..important…..where is the ammonia you mentioned coming from?
From the pic I see a favorable ammonia reading, but it could be off with my iPad screen.
What is your pH, KH, and GH of both your tank water ..and.. source of fresh new water (tap) water?
Mixing done away from actual tank water is the way to go.

Believe me when I say we all have had our moments of despair after a mistake, equipment malfunction, or mega disease. When it happens, be sad, learn from it, research options, and proceed with corrections to avoid repeating. Don’t beat yourself up over it……doing so will both take the enjoyment of the hobby away and not allow you to learn and grow. I’ve been doing this for decades and still make mistakes and am still learning/picking up new ideas. Lastly……I guarantee that not one of us was born knowing everything no matter how harshly one may respond, but the people here are pretty supportive and understanding overall.
Hey I picked up a Gh & Kh test kit, Kh is barely yellow! Gh is a lovely blueberry colour (I was expecting this to be high but been told it should settle with the water changes and I've just done more PH, Ammonia, Nitrite and Nitrate - added a new pic
 

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Cardinal tetras have a very low bio load. Before adding fish and a few (4-6 more CTs) would be fine in a 79L tank), work out any water inconsistencies and know your exact parameters. The relationship of pH, KH, GH and temperature will affect your stability and even beneficial bacteria status in a tank. Please read up on the tests for KH and GH as barely yellow and blueberry mean little as it’s the number of drops it took to change the color that gives your actual KH and GH numbers. For example…with the API test kit, count how many drops it takes to turn the blue water (initial drops) to yellow. That is your alkalinity (buffering capacity) in degrees. Telling us that number will help to determine your pH stability. Counting drops for GH is similar, but for actual water hardness which, btw, is important for CTs.

My established 33g long tank has 30 CTs in it with 12 Bentosi Tetras and a few CoryCats.
 
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Cardinal tetras have a very low bio load. Before adding fish and a few (4-6 more CTs) would be fine in a 79L tank), work out any water inconsistencies and know your exact parameters. The relationship of pH, KH, GH and temperature will affect your stability and even beneficial bacteria status in a tank. Please read up on the tests for KH and GH as barely yellow and blueberry mean little as it’s the number of drops it took to change the color that gives your actual KH and GH numbers. For example…with the API test kit, count how many drops it takes to turn the blue water (initial drops) to yellow. That is your alkalinity (buffering capacity) in degrees. Telling us that number will help to determine your pH stability. Counting drops for GH is similar, but for actual water hardness which, btw, is important for CTs.

My established 33g long tank has 30 CTs in it with 12 Bentosi Tetras and a few CoryCats.
Hey, the test kit I got doesn't give great instructions tbh so I'm even more confused
The PH I can get from the API Master Test Kit as that gives me clear info however, it doesn't include Gh and Kh..
For example, with this separate kit, Kh one says to take 5ml water and just one drop of solution, it doesn't say to keep adding drops or what to compare it to or even a breakdown of any different readings and thr Gh one isn't any better - 2 bottles, 5ml water then 2 drops from the first one sends it immediately blue then 2 drops from the 2nd bottle took it to this ribena kinda colour but again, no chart or anything I should compare it to
Should I opt for strips for this or is there a Kit you guys could recommend?
Ps, typo before it's a 70l tank
 
Imho…..no on strips. Sorry you’re having trouble w KH and GH.

Get these API test kits. They are simple to learn, are accurate, are much better than strips and have clear instructions.
IMG_2537.jpeg
 
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Imho…..no on strips. Sorry you’re having trouble w KH and GH.

Get these API test kits. They are simple to learn, are accurate, are much better than strips and have clear instructions.
View attachment 932544
Brill thanks for the tip! I'll get them ordered asap

This is the one I got earlier from the same place I stock my tank from. I didn't even think to open it and look for a colour card, you just trust that it'll have something like that but nope and God knows why cos the back of the box, and the sheet inside tell you what to do and talk about volumes and all sorts of numbers etc but they could at least leave a couple of clues to say, these colours are good but these ones not so much!

I've just watched a video on YouTube, explains it a whole lot better so that's my job for tomorrow
 

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Imho…..no on strips. Sorry you’re having trouble w KH and GH.

Get these API test kits. They are simple to learn, are accurate, are much better than strips and have clear instructions.
View attachment 932544
Forgot to ask, do they have comparison card so I can see what the numbers actually mean and the 'safe' parameters?

I read up on how to use the GH & KH kit and I hope this makes things clearer - you guys will hopefully understand the numbers

GH took 7 drops to turn blue
KH took 4 drops to turn yellow

Are these ok?

My API Master Kit gave amazing readings this time
PH 6.2 - getting there slowly
Ammonia 0.35
Nitrite 0
Nitrate 0

Thank feck!!
 
My API test for KH is number of drops until it turns from blue TO yellow. My APi test for GH is number of drops until it turns from orange TO green.

Are your tests by API? Maybe your non API tests use a different color indicator sequences. I don’t want to guess advise…..prefer to see specific results. Sorry. I am not trying to be a pain, just correcto in my understanding of your situation.
 
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My API test for KH is number of drops until it turns from blue TO yellow. My APi test for GH is number of drops until it turns from orange TO green.

Are your tests by API? Maybe your non API tests use a different color indicator sequences. I don’t want to guess advise…..prefer to see specific results. Sorry. I am not trying to be a pain, just correcto in my understanding of your situation.
I appreciate every response you give so absolutely mot being a pain at all. I don't have the api ones yet, will be around 6th Nov before they'll be delivered so I went with the one in the pic, also took a pic of the guide they gave on the box, hope this helps x

I appreciate every response you give so absolutely mot being a pain at all. I don't have the api ones yet, will be around 6th Nov before they'll be delivered so I went with the one in the pic, also took a pic of the guide they gave on the box, hope this helps x
So KH goes blue to yellow - 3/4 drops
And GH goes purple to blue - 6/7 drops
Both went to the colour required on 3rd and 6th respectively but to double double check it was correct I put an extra one on each
 

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