All my fish and inverts died overnight.

[Yotero6933]

So I woke up to the unpleasant sight of seeing pretty much all of my fish and most invertebrates dead.
2 mocha Vinci clowns
1 blood red shrimp
1 baby tomini tang
1 pink streaked wrasse
all my amphipods
emerald crabs
and possibly even my watchman goby but the tiger pistol shrimp is still moving somewhat

As of last night, everything in the tank seemed perfectly normal. My parameters were within range and no changes had been made since my scheduled water change would be on Friday. The corals seem to be perfectly fine and haven’t closed up or anything which is really odd as I would expect them to be more sensitive than the livestock. Does anyone have any idea what may have caused this to happen?

 

[Cthulukelele]

Nope, no cleaning has been done in my room in a few days. I don’t use chemicals due to my tanks.
I do have an urchin but he did survive. Besides him the only other toxic inhabitants would be the zoas/palys but like I stated in a previous post, there were no marks on them or any missing heads.

Sorry for your loss and sorry I can't be more help. That's sort of my checklist for random tank crashes. Last would be a toxic corrosion of something internal in a piece of equipment, but I'd expect a more gradual crash.

 

[Sophie"s mom]

So I woke up to the unpleasant sight of seeing pretty much all of my fish and most invertebrates dead.
2 mocha Vinci clowns
1 blood red shrimp
1 baby tomini tang
1 pink streaked wrasse
all my amphipods
emerald crabs
and possibly even my watchman goby but the tiger pistol shrimp is still moving somewhat

As of last night, everything in the tank seemed perfectly normal. My parameters were within range and no changes had been made since my scheduled water change would be on Friday. The corals seem to be perfectly fine and haven’t closed up or anything which is really odd as I would expect them to be more sensitive than the livestock. Does anyone have any idea what may have caused this to happen?

We had a tank set up at my work once and this happened. We pretty much determined that when someone was doing some cleaning, something must have accidently been sprayed too close to the tank or something. That would certainly do something like this.

 

[exnisstech]

did any equipment send stray voltage into it

Stray voltage is a red herring and does not harm livestock. This has been discussed and confirmed by @Jay Hemdal. I have also confirmed this in my own tanks. I had 50 volts in a tank once and all livestock was perfectly fine.
To the OP I'm sorry this happened and I have nothing to offer. My reply was simply because stray voltage always seems to get brought up when mysterious deaths happen and people need to look elsewhere for the cause.

 

[jkcoral]

Stray voltage could still be a culprit, and the finger test shouldn’t rule it out. You could head to a local hardware store or something and grab a meter for prettt cheap to check.

And @Sophie"s mom made a good point. I had a friend that was out of town, and his significant other was doing some spring cleaning and the chemicals being too close to the tank (and used on the glass) caused huge problems and an almost total tank crash.

 

[jkcoral]

Stray voltage is a red herring and does not harm livestock. This has been discussed and confirmed by @Jay Hemdal. I have also confirmed this in my own tanks. I had 50 volts in a tank once and all livestock was perfectly fine.
To the OP I'm sorry this happened and I have nothing to offer. My reply was simply because stray voltage always seems to get brought up when mysterious deaths happen and people need to look elsewhere for the cause.

That’s really interesting. Been in the hobby a long, long time and never heard that. You learn something new every day!

 

[Idech]

Did you clean or disturb the sand before it happened ?

 

[exnisstech]

That’s really interesting. Been in the hobby a long, long time and never heard that. You learn something new every day!

I looked it when I had the high voltage in my tank. I didnt know it untill I stuck my hand in the tank. I was standing on a chair and fell off when I jerked after getting shocked. I measured just over 50 volts from two leaking hydor koralia power heads and all livestock including inverts and coral were perfectly fine.

 

[Yotero6933]

Did you clean or disturb the sand before it happened ?

Haven’t cleaned it since the next maintenance would be on Friday. I’m honestly at a loss, but I appreciate all your inputs. I will be heading to college in a few minutes, so I’ll read new responses soon

 

[Bruttall]

That’s really interesting. Been in the hobby a long, long time and never heard that. You learn something new every day!

The reason voltage in the tank won't hurt the stuff inside the tank is because that stuff never gets Grounded. In order for the Current to Hurt you, a GROUND must be established. You can actually test this yourself if you have a bad heater element that you know shocks you. Put on rubber sole shoes and put your hand back in the water. no shock because you are Insulated and Not Grounded.


Not to mention Lightning strikes the Ocean. Water is a conductor of electricity and those fish keep on surviving.

 

[BeanAnimal]

Stray voltage could still be a culprit, and the finger test shouldn’t rule it out. You could head to a local hardware store or something and grab a meter for prettt cheap to check.

There is no such thing as "stray voltage"
There is potential and current.
Current flow must have a source and a destination (ground).
In our aquariums that is either induced (magnetic fields) or direct form a piece of bad insulation. In either case, the presence of voltage means absolutely nothing unless it has someplace of lower potential to complete the circuit. Example, a ground probe, a grounded metal heater, etc.

Lets say that a lower potential path IS available and current does flow in the tank. Current typically does not flow THROUGH fish, but around them in saltwater. Saltwater is a very good conductor, fish have high resistance. It takes HIGH current to flow enough of it through the fish to stun or harm them. We are talking many tens of amps, not a few mA of even a few amps from induced voltage/current leaking to a heater ground or similar. You are in far greater danger than you fish, as it only takes a few mA to stop your heart.

 

[BeanAnimal]

The reason voltage in the tank won't hurt the stuff inside the tank is because that stuff never gets Grounded. In order for the Current to Hurt you, a GROUND must be established. You can actually test this yourself if you have a bad heater element that you know shocks you. Put on rubber sole shoes and put your hand back in the water. no shock because you are Insulated and Not Grounded.


Not to mention Lightning strikes the Ocean. Water is a conductor of electricity and those fish keep on surviving.

See above - not only do we need a ground, but we need pretty darn high current flow for enough to flow through a fish to harm it. I would imagine long term, low current could cause stress, lateral line problems, etc. But this would not result in a mass extinction event in the tank...

 

[rhduggan]

I looked it when I had the high voltage in my tank. I didnt know it untill I stuck my hand in the tank. I was standing on a chair and fell off when I jerked after getting shocked. I measured just over 50 volts from two leaking hydor koralia power heads and all livestock including inverts and coral were perfectly fine.

This just makes sense. If there is "voltage" in the aquarium that just means there is potential there; it doesn't mean there is current flowing through the animals in the tank. Just like a bird sitting on an uninsulated high-tension line, the bird and the line are at the same potential, which could be 1.5 k volts. The bird feels nothing (unless something else comes along to conduct that voltage to ground or another line in which case poof!). When you put your hand in the tank, you became that path to ground and got whacked.

 

[BeanAnimal]

Haven’t cleaned it since the next maintenance would be on Friday. I’m honestly at a loss, but I appreciate all your inputs. I will be heading to college in a few minutes, so I’ll read new responses soon

Does your flow vary in the evening? It sounds like low oxygen and possibly a small bacterial bloom (cause or effect, I don't know). What do you dose and how and what do you feed, etc.

 

[rhduggan]

Do you have sea cucumbers in your tank?

 

[MnFish1]

There have been a lot of good ideas - I'm still a bit confused. You said in the OP that you lost 'pretty much' all of your fish and invertebrates, but that your corals and an urchin are ok? Which fish are ok - how do they look - do they have any symptoms.

Usually if everything is killed it's a toxic issue, and as others have said stray voltage should not be an issue this quickly. Though the tank has been set up for a year - when did you last add a fish, etc or do a water change?

IMHO - IF you corals are ok it could be that one of your fish died, causing a bacterial issue or ammonia issue leading to more deaths. Different fish and corals are more / less sensitive to ammonia issues.

With invertebrates dying, it's nearly unheard of that the fish are dying of a parasite, etc.

Though there have been stories about various cleaning products causing problems (more likely in much smaller tanks) - I think this is rather rare with larger tanks due to that amounts of chemicals involved.

 

[Jay Hemdal]

See above - not only do we need a ground, but we need pretty darn high current flow for enough to flow through a fish to harm it. I would imagine long term, low current could cause stress, lateral line problems, etc. But this would not result in a mass extinction event in the tank...

I try to make the distinction between "induced voltage" and "short circuit". The former being low, measurable AC voltage created by various pumps in their normal operation. The latter is higher current/voltage created by some equipment malfunction. I always presume that when people say "stray voltage" they mean the first. You cannot even detect that unless you ground your probe, almost like the act of measuring for it produces it. I don't have any sense on how DC would figure into this though.

In my HLLE study, we fairly conclusively ruled out "induced voltage" as a cause for that.

Jay

 

[Jay Hemdal]

So I woke up to the unpleasant sight of seeing pretty much all of my fish and most invertebrates dead.
2 mocha Vinci clowns
1 blood red shrimp
1 baby tomini tang
1 pink streaked wrasse
all my amphipods
emerald crabs
and possibly even my watchman goby but the tiger pistol shrimp is still moving somewhat

As of last night, everything in the tank seemed perfectly normal. My parameters were within range and no changes had been made since my scheduled water change would be on Friday. The corals seem to be perfectly fine and haven’t closed up or anything which is really odd as I would expect them to be more sensitive than the livestock. Does anyone have any idea what may have caused this to happen?

Just off the cuff, this sounds very much like a transient low oxygen event. Corals and some other invertebrates have lower oxygen requirements, while fish and crustaceans have higher needs. With these events, the fish and shrimp die first, followed by other crustaceans and echinoderms. Snails usually just close up and corals are often fine. In very severe events, of long duration, everything dies. In really short duration events, perhaps on the most sensitive fish (wrasses) may be affected.

So what can cause this? Impossible to say for sure, it depends on too many factors. Certainly a power outage is a main cause. You can even have a pump seize up and then works itself free. Some people mentioned dead animals causing a cascade - that is because the bacteria growing on the dead animal's body consume all the oxygen. I had one case recently, where the person topped their tank up with freshwater and all the fish died from lack of oxygen. How? Well, they did not have any aeration in the tank. They didn't know it, but the fish were relying on the meager gas exchange created by the splashing water returning to the tank from their HOB filter. When they topped the tank up, no splashing and the oxygen level dropped!

Jay

 

[Tsquared]

Grap an ICP test from the LFS if possible. It may lead to a clue.

 

[brandon429]

Why is disease caused loss initiated by fish kill ruled out here

What steps were taken to avoid disease wipeouts

Do you have tight import control over diseases by fallow preps etc and the losses excluded corals it seems, at least when water quality is reinstated

 

[BeanAnimal]

I try to make the distinction between "induced voltage" and "short circuit". The former being low, measurable AC voltage created by various pumps in their normal operation. The latter is higher current/voltage created by some equipment malfunction. I always presume that when people say "stray voltage" they mean the first. You cannot even detect that unless you ground your probe, almost like the act of measuring for it produces it. I don't have any sense on how DC would figure into this though.

In my HLLE study, we fairly conclusively ruled out "induced voltage" as a cause for that.

Jay

Hi Jay - I don’t distinguish between the two (but understand your explanation and why you do).

I simplify, as to me current either flows or it does not (let’s ignore galvanic reactions and ionic charge transfer). If current flows, the question then becomes how much through the fish and how much around the fish, regardless of the source.

HLLE - I have not read the study but will. At what current level do fish begin to feel the current, or sense it, or transition from sensing to being bothered or stressed, let alone short term or long term damages or affected, I don’t know. The only thing that I do know is that given Ohm’s law and Kirchhoff’s, it would take one heck of a lot of current in the tank to produce even a few mA of current in a fish.

Thanks for the response. BTW,