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?

 

[The_Paradox]

Need more details to even take a guess. How old is tank, when was everything added, what are your actual parameters including temp and salinity, etc.

 

[ryanjohn1]

How old is tank. When was it cycled. What were your test numbers?

 

[CasperOe]

It could a variety of things I'm afraid, it does however take a rather large disturbance to do that to a tank over night.

Is it an old established tank, or a rather new one?

Did you check your parameters this morning - mainly ammonia? An ammonia spike can cause this sadly.

 

[Yotero6933]

How old is tank. When was it cycled. What were your test numbers?

Tank would’ve been a year old on may 5th
Salt 1.025
Alk 10.55 dkH
Mg 1530 ppm
Ca 440 mg/l
The test kit I use is the aquaforrest titration kit.
Edit: temperature was at 78 F

 

[threebuoys]

Definitely need more info.

How long has the tank been cycled? When were the fish added? Have you added any chemicals to the tank? What is the ammonia level?

Such rapid and complete death certainly suggests a very toxic situation. Ammonia or some other toxic chemical or possibly very low oxygen, very high temperature, salinity very low or very high come to mind.

 

[jkcoral]

Really sorry to hear about your losses. That is a bummer :/

Without any more information, it’s hard to guess what could’ve caused so many issues so quickly. As someone else noted, it could’ve been an ammonia spike (but one that severe happening out of nowhere would be strange in an established tank). Makes me wonder if there was a mechanical failure, like the pumps/flow being cut off for a certain number of hours or if there was some stray voltage from a faulty piece of equipment.

 

[Yotero6933]

It could a variety of things I'm afraid, it does however take a rather large disturbance to do that to a tank over night.

Is it an old established tank, or a rather new one?

Did you check your parameters this morning - mainly ammonia? An ammonia spike can cause this sadly.

It was almost a year old, so it would be weird to have a sudden ammonia spike.

 

[CasperOe]

Tank would’ve been a year old on may 5th
Salt 1.025
Alk 10.55 dkH
Mg 1530 ppm
Ca 440 mg/l
The test kit I use is the aquaforrest titration kit.

My best bet if you can eliminate equipment failure is that something died and caused an ammonia spike If that happens, it can cause a bad chain reaction.

Is rather odd in an established tank though..

 

[ryanjohn1]

Tank would’ve been a year old on may 5th
Salt 1.025
Alk 10.55 dkH
Mg 1530 ppm
Ca 440 mg/l
The test kit I use is the aquaforrest titration kit.

Ok so it’s not a new tank. Did the heater malfunction or did any equipment send stray voltage into it

 

[Yotero6933]

Ok so it’s not a new tank. Did the heater malfunction or did any equipment send stray voltage into it

I don’t think it’s stray voltage because I put my finger in the water to check if that was a possibility, but I didn’t feel any shock. The pumps seem to be running fine which really is making me question what it could be. At first I blamed my zoas, but there were no marks on them and all the polyps were present. For reference, I checked my tank at 1am last night and things seemed fine, but they were dead by 8am.

 

[Coalminer]

Did you test ammonia, nitrite, nitrate?

 

[Cthulukelele]

How did the tank look visually the night before

 

[Yotero6933]

How did the tank look visually the night before

Visually I could see the amphipods, hermit crabs, snails and bristle worms moving about and feeding which wasn’t out of the ordinary. The fish were sleeping in their normal areas but swam a bit because my phones flashlight was on. The water was crystal clear before I went to sleep.

Now the water is slightly hazy so there is ammonia most likely due to all of the dead inhabitants. Nitrites were at zero and nitrates were at around 6.5.

 

[Cthulukelele]

A massive bacterial bloom can deoxygenate water which can asphyxiate all the critters in the tank. A large fish dying can start it and each death makes it worse. That also makes water hazy

 

[ryanjohn1]

I don’t think it’s stray voltage because I put my finger in the water to check if that was a possibility, but I didn’t feel any shock. The pumps seem to be running fine which really is making me question what it could be. At first I blamed my zoas, but there were no marks on them and all the polyps were present. For reference, I checked my tank at 1am last night and things seemed fine, but they were dead by 8am.

Heater working properly?

 

[Yotero6933]

A massive bacterial bloom can deoxygenate water which can asphyxiate all the critters in the tank. A large fish dying can start it and each death makes it worse. That also makes water hazy

 

[Yotero6933]

Heater working properly?

The water isn’t out of its range and I haven’t been shocked by anything so I would assume it is working fine.

 

[Cthulukelele]

The water isn’t out of its range and I haven’t been shocked by anything so I would assume it is working fine.

Honestly that tank isn't cloudy enough imo for it to be a massive bacterial bloom and all your corals are still happy. My guess would be some sort of toxin in the tank. Have any sea cucumbers/other toxic creatures? Did you do any irl cleaning with cleansers around the tank yesterday?

 

[Yotero6933]

Honestly that tank isn't cloudy enough imo for it to be a massive bacterial bloom and all your corals are still happy. My guess would be some sort of toxin in the tank. Have any sea cucumbers/other toxic creatures? Did you do any irl cleaning with cleansers around the tank yesterday?

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.