Help! All the fish are dead...

[savingnemo754]

Ok a friend of mine called me this morning and told me all her fish died last night. I checked her water and this is what them are:

Salinity: 1.020
Nitrate: 0.00
Nitrite: 0.50
Ammonia: 0.00
Phosphate: 0.00

The fish ate well last night and show no signs of ick, velvet, or parasites. All corals are doing great open and happy. The tank is a 120 high with 2 rena XP3 filters on it. Maintenance was done yesterday which consisted with cleaning 1 of the filters and a 20% water change.

I've been in the hobby for 5 years and this has me flustered. Anyone have any ideas.

 

[weaglereefer]

What kind of test kits? How long has the tank been set up? How did you "clean" the filters? What is the S.G. normally? Is it possible a water change was done with RO only and not salt?

 

[jmaneyapanda]

Nitrite is toxic. And if there is nitrite now, there was ammonia recently. Im guessing this tank hasnt cycled or has crashed. Either way, there is toxic elements in the water.

 

[savingnemo754]

Nope I actually did the water change for her and had plenty of salt. The salinity was a little low and we had planed on slowly increasing it over the next week or so. The test kits were API for nitrite and Elos on the rest.

 

[savingnemo754]

Oh Yeah the tank has been set up for about 8 months and the filters were just rinsed with RO water. The nitrite wasn't there 2 days ago it was all good in all depts. The fish were a Yellow Tang, Blue Hippo Tang, Social fairy Wrasse, and 2 clowns.

 

[savingnemo754]

Panda

Would that little nitrite kill all the fish that quick?

I've had tanks the had .5 nitrite and nitrate and some phosphates with no losses.

I guess it is just shocking to me that just a little nitrite would kill everything that quick.

 

[savingnemo754]

I didn't think about electricity!!

I will check tomorrow when I can get over there.

 

[jesspete]

what about temperature?

 

[savingnemo754]

80

 

[jmaneyapanda]

Nitrite is toxic. It doesnt take a lot to kill. The only way for nitrite to be there is if ammonia was there. Both are fish killers. I am guessing that is the issue. There should not be ammonia or nitrite in the system, especially an established system. If it is there, then something destroyed the nitrfying bacterial population. Maybe the RO rinse. I dont know, but I do know that nitrite should be zero. Who knows what the nitrite was the day before, when the fish died, too.

 

[jmaneyapanda]

ares;334703 wrote: something with the water change caused it. chemical residue in the mixing bucket or something. nitrite is toxic sure... so is ammonia. but more likely that the .5 of nitrate came after the fish's death than before.

Id suspect something you arent testing, such as chemicals that could somehow have been introduced.

even electricity leaking ussually wont kill a fish like that. it will bother them, but not just straight up keel over instant death...

Disagree. A *rotting* fish would cause a ammonia/nitrite surge. Not a recently dead fish. Either way, a nitrifying filter shouldve easily accomodated it in an established tank.

 

[savingnemo754]

ares;334704 wrote: also, it was hot yesterday, do you know how hot the tank may have gotten? perhaps 80 now was 90 at peak hours yesterday?

Thats a good point. I will have her watch the temp today and see how high it gets.

 

[savingnemo754]

jmaneyapanda;334705 wrote: Disagree. A *rotting* fish would cause a ammonia/nitrite surge. Not a recently dead fish. Either way, a nitrifying filter shouldve easily accomodated it in an established tank.

Both are right we honestly have no idea what the levels were "yesterday" when the damage was done.

Whatever happened it cause a "mini cycle" and that most likely killed them. The temp may have been a contributing element with it being the beginning of the hot season. Might have her add a fan just to be on the safe side right now.

 

[leslie]

We had a similar situation when I cleaned a rock with a toothbrush to remove algae and rinsed in RO instead of salt water. Killing the bacteria on that rock created a mini cycle overnight and we lost some fish, though not all. At least, that's all we could figure out had happened.

Now I rinse everything in salt water....

 

[jennm]

Toxin. That's the first thing I think of. It wouldn't show up in the chemistry (except sometimes phosphate is a "marker" for stuff like Febreeze or vaporizing air fresheners).

Could someone with their hands in the tank have had lotion or something on their hands?

I've seen that happen plenty of times.

Jenn

 

[dakota9]

JennM;334731 wrote: Toxin. That's the first thing I think of. It wouldn't show up in the chemistry (except sometimes phosphate is a "marker" for stuff like Febreeze or vaporizing air fresheners).

Could someone with their hands in the tank have had lotion or something on their hands?

I've seen that happen plenty of times.

Jenn

Agree with Jenn here, it happened to me after I cleaned my last FW tank with a brand new sponge which was treated with an anti-bacterial agent .

The nitrite certainly didn't kill all the fish. Ammonia is more toxic, and the fish would have died with high levels of ammonia in the tank. In the old days, we cycled with fish, and many hearty speciems (Damsels, Clowns) handled it very well. I cycled 2 different tanks with the same damsel once. He was fine.

Something happened before, during, after or because of the servicing that was done yesterday. The 2 of you retrace your steps, maybe something will come to light.

 

[dakota9]

Leslie;334714 wrote: We had a similar situation when I cleaned a rock with a toothbrush to remove algae and rinsed in RO instead of salt water. Killing the bacteria on that rock created a mini cycle overnight and we lost some fish, though not all. At least, that's all we could figure out had happened.

Now I rinse everything in salt water....

See? I'm still not sold on this explanation. As I remember, this was a comparatively small rock. If this happened in a 10 gallon nano, then it's within the realm of possibility, but in the past, I've intentionally put one nice piece of uncured LR in my old 30 gallon set-up to cure, with no ill effects.

I think these are similar situations where unknown toxins came in to play.

 

[jennm]

I'm not convinced that the nitrite test is valid. Ammonia would have preceeded it. What brand of test kit was used?

It does not take much of a toxin to do this. Febreeze and air fresheners (ie "plug-ins") can do it, soap or lotion etc., on hands, carpet powder (the kind you sprinkle on and vacuum up), Windex or similar if sprayed/vaporized in close proximity (although that usually shows up as ammonia first)... any/all of these can cause it.

Electricity is a possibility too - but usually that starts a disease (like ich) or just the most sensitive fish show signs of stress or lateral line -- takes a big zap to kill a bunch of fish.

So, IMO, some sort of toxin is the prime suspect. WATER CHANGE, add a Polyfilter (which pulls a variety of nasties out)... and be very careful about what is in or around the tank.

Jenn

 

[jennm]

Leslie;334714 wrote: We had a similar situation when I cleaned a rock with a toothbrush to remove algae and rinsed in RO instead of salt water. Killing the bacteria on that rock created a mini cycle overnight and we lost some fish, though not all. At least, that's all we could figure out had happened.

Now I rinse everything in salt water....

I don't think that's enough of a disturbance either - was the toothbrush new? Flouride is deadly.

A small disturbance in the biological like that won't cause a wipe-out. Mother Nature is not that fragile. I'd lean toward toxin in this instance too.

Jenn

 

[dannybradley]

Nitrite is the waste product of ammonia being metabolized by nitrosonomas. Ammonia does physical damage to the fish by burning the gill plate, reducing the amount of oxygen entering the blood.

Nitrite bonds with red blood cells faster than oxygen can. It kills through asphyxiation. Both are very toxic. Ammonia has the edge in saltwater because of the high pH. The lower the pH, the more hydrogen ions you have present in the water. These bond with NH3- to form NH4+(ammonium), which is significantly less toxic to fish.

Never rinse biological filter media, and this includes your sponges, with anything other than tank water. It's very easy to do this during a water change. Even fresh saltwater can kill bacteria because of the sudden change in environment. Because the osmotic pressure is so different between saltwater and freshwater, putting a living organism in a hypotonic soltution from a hypertonic solution the freshwater rapidly enters the cell, causing it to rupture.

It sounds like you wiped out the biofilter causing an ammonia spike and subsequent nitrite spike. In addtion to that, those two Rena probably don't move enough water around the tank, causing low O2 levels, which only compounds the issue of NH3 and NO2 present. Also, deep tanks almost always have O2 issues due to the small surface area. One final thing- fish hide when NH3 and NO2 are stressing them out, many times at the bottom. NH3 is heavy and rests towards the bottom of the tank. Taking a sample from the bottom will yield a high amount of ammonia than one taken from the top.

Sorry for your friend's loss.