All fish dead after water change - what went wrong?

[brandon429]

@taricha

I've found a new aspect of cycling I wish you'd test one day with the digital setup you have for ammonia

=do reef tanks store ammonia in the sandbed or in the rocks, where it can be liberated deadly upon disturbance of the substrates (popular opinion says yes)

I predict = no they don't its a metabolic compound exuded by animal cells or exceptional pockets of decay/protein digestion from bacteria/ and is instantly used up in proximity of production by plants or other life forms yielding none to kill fish or life when funky sandbeds are disturbed. the killer is something other than ammonia is my bet.

reef tanks don't store ammonia, cells emit it live-time and there's no source hiding in a 3 month old tank setup to liberate it from the substrate.

I haven't seen any seneye posts tied to people disturbing their tank to check for nh3 spikes

I predict ammonia is constantly blamed for things it didn't do in the reef tank.

add substrate-caused cycle stalls to the list of things we're never going to uncover without digital testing.

 

[brandon429]

also factors: there must be over ten thousand examples anyone can search of in-tank work causing a noted ammonia spike on API (just never a digital setup) <----that is precisely where the notion that moving rocks around releases pent up ammonia in a reef tank, it's old cycling science clue #319

discovering what causes those spikes if not actually ammonia could do real helpful work for api owners who are shy of even moving a single rock around in the tank for fear of generating ammonia, as if the sandbed is full of it just waiting to be released

because this tank is so new/barren white/ we aren't going to be able to find the causes here in my opinion. we've got api + a new tank and no disease preps taken whatsoever such as fallow and quarantine (of all additions, not just fish)

too many variables in play to decide what caused the losses.

 

[Fritz05]

What has been the temperature of your new salt water when doing water changes?

+1 on the temperature.

 

[KrisReef]

Don't know why they would spike it but they do occasionally switch from chlorine to chloramine and not tell you about it.

Probably when they detect e. coli in the tap water supply. "A little bad tasting water isn't gonna cause many problems but a little e. coli could cause another COVID-19 run on toilet paper."

 

[Debramb]

Our Ro/DI has to work hard on calcium removal from our 200+ deep well in Limestone! Fort Worth Tx was at one time a seabed. Husband had to literally jackhammer to put sprinklers in. Have found beautiful fossil shells, haven’t added to tank.
Debra

 

[Stigigemla]

I wonder about Your cleaning the rocks. You wrote you used a tooth brush but did You use water. Salt or tap water? Tap water could have killed some of the bacteria in the stone to cause an ammonia peak. And if You mixed in hot water it could contain a lot of cupper.
If you are using a hand cream to keep your skin soft be aware that some of them are very poisonous to fish and corals. Containing zinc that sometimes help to heal small wounds.

 

[schooncw]

Here’s my take: When you have a tank with a light bioload, low nutrients and immature rock and then impart a massive “pollution” event, you’re probably going to have an ammonia spike because even though your tank is cycled, it’s only cycled to keep up with a near pristine tank and barely any waste being produced. IME, dirty and more mature tanks are FAR more resilient to this happening because the beneficial bacteria population is so robust and can better cope with ammonia spikes. In all honesty, you WANT your rocks to initially be covered in algae. You WANT diatoms on your sand in the beginning. I consider that a badge of honor because it’s all part of the process to have a healthy tank in most cases and both conditions are easily remedied in a mature tank.

Excellent observations! The rock in my 120 LPS/Softie tank is 30 or so years old-all live-and I have always done regular water changes but, whether tap or RO, always, always add Prime.

 

[schooncw]

Did you start your system with any "real" live rock? To me, this is an absolute imperative, not only for biodiversity but for system maturity and stability.
If you do not have live rock in your system, I would add some.

 

[exnisstech]

I wonder about Your cleaning the rocks. You wrote you used a tooth brush but did You use water. Salt or tap water? Tap water could have killed some of the bacteria in the stone to cause an ammonia peak.

I was just getting ready to ask the same thing.

EDIT :FWIW I would never pull and scrub rock on a 3 month old system. I'm no expert but IMO tanks need to mature and develop bacteria good and bad, algae etc it's just how it works. I think scrubbing the rocks may stall that process causing more harm than good. Like I said tho I'm no expert just my way of thinking which is not always correct.

 

[Randy Holmes-Farley]

-and I have always done regular water changes but, whether tap or RO, always, always add Prime.

For what hoped-for purpose?

 

[blecki]

It does actually dechlorinate doesn't it?

 

[Randy Holmes-Farley]

It does actually dechlorinate doesn't it?

Is that needed on RO water?

 

[Randy Holmes-Farley]

FWIW, it seems folks have this idea that Prime contains some some benign secret chemical that can only do good.

I personally take Seachem product claims as aspirational rather than accepted fact since they sometimes seem to fall apart under scientific scrutiny, but even if you believe that Prime "detoxifies" heavy metals, that should send a warning sign that, if true, means it may be lowering the bioavailability of needed heavy metals (copper, iron, nickel, etc.). It is certainly able change the form of many trace metals to a more reduced oxidation state since it is a reducing agent. Is that a problem? I do not know. It might even be beneficial, but it is not just an innocent bystander.

 

[DCR]

I use Prime on my freshwater tanks to dechlorinate when doing water changes. I think it does work for neutralizing both chlorine and chloroamine. I used not to think it was necessary on just a water change, but I had a couple of events where I wiped out a tank after a water change due to high levels of chloramine and bleach in the tap water that I use (one water system used chloramine and one uses bleach to disinfect the water). I don't think it should be necessary for RO water and do not use it on my saltwater RO reservoirs. It has a sulfur like smell so I think it has some reducing agents in it.

 

[taricha]

@taricha

I've found a new aspect of cycling I wish you'd test one day with the digital setup you have for ammonia

=do reef tanks store ammonia in the sandbed or in the rocks, where it can be liberated deadly upon disturbance of the substrates (popular opinion says yes)

I've actually looked at this a decent amount. I poked and prodded aquarium sand and the porewater a number of different ways to try to make it reveal the goodies that drives sandbed nuisance growth.
There's a bit there in old sand but not enough to be exciting.
The ammonia in the porewater might be a few tenths higher than in the bulk tankwater. Could be enough to help nuisance sandbed algae a little bit, but nowhere near amounts that could harm fish etc if it was liberated by stirring.
If you are looking for a fish-killing bogeyman hiding in old sandbeds/porewater, it's not ammonia you want to track - it's ORP and dissolved O2. Not only does my old sandbed have no O2 in it, it has negative ORP, sulfur smell, and when mixed with aerated tank water - the sandbed/porewater can actually consume O2 from the tank water. So there are some very low redox things including H2S, maybe others, which can be bad news if released all at once.

 

[brandon429]

very nice to know I'd never seen it looked at before via measurement, really good to know/note taken

 

[Randy Holmes-Farley]

I use Prime on my freshwater tanks to dechlorinate when doing water changes. I think it does work for neutralizing both chlorine and chloroamine. I used not to think it was necessary on just a water change, but I had a couple of events where I wiped out a tank after a water change due to high levels of chloramine and bleach in the tap water that I use (one water system used chloramine and one uses bleach to disinfect the water). I don't think it should be necessary for RO water and do not use it on my saltwater RO reservoirs. It has a sulfur like smell so I think it has some reducing agents in it.

I certainly do not dispute the need to remove chlorine or chloramine before using tap water, and Prime may be fine for that.

 

[Seanb1]

Did you check your rodi water for chlorine/chloramine with a real chlorine test kit.
Chlorine can get past em easily.
I remember having this exact discussion with one of the guys from ro guys a long time ago and he said he's always suspected alot of unexplained fish deaths come from people believing that their ro filter was capable of completely removing it.
It only takes 1 ppm to kill fish.

 

[steelrain119]

Honestly your tank is new things happen fish die, it sucks. Personally you should have never scrubbed your rocks. Your tank is maturing and going though the ugly phase. It is going to look good then look like dog poop. Ride the wave and stick with it. You are going to get frustrated but it is the hobby. At 2 months old I would suggest against putting corals in or anything that really costs money. I am the most impatient person and have made all the mistakes. Trust me go out buy some cheep fish and stick with it.

 

[Randy Holmes-Farley]

Did you check your rodi water for chlorine/chloramine with a real chlorine test kit.
Chlorine can get past em easily.
I remember having this exact discussion with one of the guys from ro guys a long time ago and he said he's always suspected alot of unexplained fish deaths come from people believing that their ro filter was capable of completely removing it.
It only takes 1 ppm to kill fish.

IMO, it would be rare to get 1 ppm chlorine through an RO/Di. And then you'd have to do a huge water change to approach that level in the tank.

have you ever seen a measurement from someone that did show that much chlorine getting through an RO/DI?

Testing is certainly cheap and easy, and anyone concerned should do it, but I also think it is among the less likely issues.