Complete wipeout

[popsock]

I went to bed last night leaving my 150 litre deep-water reef tank looking all fine, and dosed some Seachem Calcium Gluconate into the tank before I did.

This morning every single fish is dead/vanished. There appears to be no sign of fish life whatsoever!

Every invert/coral is perfectly OK, some looking better than usual.

The water was cloudy, but has now cleared completely. The reason I mentioned the Seachem product is that it makes the water cloudy (nothing else I add does). Also, as its glucose based I wondered if it could feed bacteria into a frenzy?

hmmmmm. I've never lost so many fish in so short a time. If anyone knows what this could be I'd be very interested.
Cheers
Andy

[SDguy]

So are they dead or missing?

[artman18944]

if there was a bacterial bloom i wonder if that could have caused the O2 levels to drop low enough to kill the fish?

[ashrem]

Need water parameters to see if anyting else is out of the ordinary.

[maro1]

Sounds Like an X-File case

Mar

[msman825]

are the fish bandit hit

[twon8]

are you running a skimmer?

some tank details would help

[terryp01]

I'm with SDguy. Are they missing (you cannot find the bodies) or are they dead? What type of fish did you have and what size?

I have had them disappear only to show up in the sump but never disappear all at once.

[popsock]

Tank is 150 litres as said. About 20kg of liverock. Only 2-3 months old. Skimmer runs for 3 hours in the morning, but I've only been doing that for the past week. Wonder if I should have left it off?

The tank is a deep water experiment in keeping the water params high, but as 'dirty' as possible for coral growth, especially dendronephthea etc. So far so good, under just 48w of light the coral growth both hard and soft is amazing. The tank is quite heavily fed.

however, the params 2 days before the disaster were:
pH 7.8, salinity 1.024, nitrate 20ppm, nitrite 0.0, ammonia 0, temp solid 23.8, calcium 420, dkH 8.0. Oxygen was tested a month previous as I was concerned about that, and it was about 5ppm. However, it was tested with a Salifert test kit and they're not that hot for oxygen (good for everything else though).

Since this morning 3 fish have appeared, and one body has been removed. There is a chance that other fish are lurking in there for some reason.

[Sheol]

7.8 seems a bit low for a reef tank..
Condolences on your losses. It might have something to do with the tank still being relatively new ( I will never add another angelfish to any system less than 6 months old, IE.)

Matthew

[twon8]

i would leave your skimmer on all the time, if o2 is depleted the skimmer will keep putting it into the water.

[snorvich]

I agree with the suggestion of running the skimmer all of the time; also the PH seems fairly low for a reef tank. Everything else seems ok.

[popsock]

The tank ran fine for 2 months. If O2 was an issue it would have shown long before this. There is no sump.

Three fish are alive. One is dead. Four are missing. three of them are 1" carib. bass, the other is a blackcap basslet.

Whilst running a skimmer all the time might help if it was indeed an O2 problem, it would defeat the entire object of setting up the tank in the first place, ie. to attempt to grow non-photosynthetic corals.

I do remember one other thing that could explain this event. I added two bags of live rotifers to the tank without sieving them. It's quite possible that the water they were in was toxic in some way, although they were certainly mostly alive when I put them in.

[twon8]

i run a skimmer 24/7 and grow tubastreas, micros, blastos; just feed more,

glucanate is glucose based, which is a sugar--> sugar will cause a bacteria bloom, and the bacteria will use up all the o2; during the day your corals are releasing o2 into the water via photosynthesis, but at night they don't, and losing a bunch of fish at once sounds to me like an o2 issue

[twon8]

im betting since its deep water you don't have a whole lot of flow?

[zrs6v4]

I dont see how any of your levels would have killed your fish that quick.. maybe no oxygen.. did you find them yet? if not could something other than your dosage of searchem have been dropped in yuor water? I would say if you have a wrasse then it could be burrowed in the sand.. my buddies wrasses both play dead in the sand when scared or messed with.. i dunno Im just talkin.. good luck

[Chad Vossen]

a shot in the dark, but do you have a cat? i have noticed my cat watching my clownfish and sometimes wonder what he is planning.

otherwise a O2 drop sounds reasonable.

[Chad Vossen]

also, i dont think the rotifers had anything to do with this, in my experience i have noticed that rotifers are sensitive. if the water they are in was toxin enough to harm your fish, you would have had alot of dead rotifers as well.

[Wolverine]

Do you use Purell or any of those other alcohol-based hand-sanitizers?

Dave

[popsock]

Hi Dave, no I don't mate.
Cheers

[JHemdal]

popsock,

I've lost fish to low DO (after dosing praziquantel with ethanol as the solvent). In EVERY case, the dead fish died with their mouth's fixed wide open (to use an old US reference - like Mr. Bill on SNL TV show back in the 1970's). Obviously, the missing fish could look like this or not - but what about the one body you did recover? Low DO would probably cause many of the inverts to close up also, and you didn't mention that......


Jay Hemdal

[amuruges]

<a href=showthread.php?s=&postid=8816784#post8816784 target=_blank>Originally posted</a> by artman18944
if there was a bacterial bloom i wonder if that could have caused the O2 levels to drop low enough to kill the fish?

A few months ago, the breaker tripped in the middle of the night and all my pumps where down for 8 hrs, I lost 5 anthias, one powder blue tang and a six line wrasse, my black clown pair, purple tang and my lawnmower survived, all my inverts were fine and my corals, all sps showed no ill effects. I would support artman's theory, my orp was at 120.... That was a sad day for me, I feel your pain.