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?

 

[Doompastew]

Update on everything, it’s probably safe to say that the cause of death was related to a depletion in oxygen. My outflow nozzle was lower than normal which was weird, but paired with no protein skimmer the surface biofilm must have been an issue. Why did it become a problem on that one specific day, I’m unsure, but as of now I have fixed the issues and created more surface agitation.

Also to those that asked what size tank, it is a fluval 13.5, and I understand that a tank of that size is not ideal for a tomini tang. He was a baby and only measured about 1.5 inches so I was going to grow him out before adding him to my larger display tank.

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?

Are you in an apartment or a townouse? I had an incident in a townhouse where the neighbor used fleabombs. I had freshwater at the time. The results sounded the same as yours, total loss. 8 hours is a short time for anything other than toxins. Just a thought.