Please help with loss of all fish

[Merie]

Hi,
I am totally new to fish tanks much less a reef, but I jumped in anyway. So here is the problem, I lost all of my fish in a 4 hour period overnight. I have a 42 gal. hexagon tank with about a 3" sand bed and 50 lbs live rock. After cycling, I started with a blue chromis which did awesome, then added a striped chromis, then a cleaner shrimp which also did awesome, and 9 hermit crabs and 9 snails. Then I went on vacation a couple of weeks ago and brought back 2 small sand dollars and about 20 baby conchs and added them. All were doing great and then last Thursday I added a lawnmower blenny and a yellow faced goby along with another hermit crab and a new narcisis snail that burrowed into the sand and I never saw it again until yesterday morning. Anyway on Sunday I tried to use a 10 gallon tank my girlfriend gave me to put all my equipment in (protein skimmer & uv light power head), it didn't work (haven't figured out why yet) so I put everything back in my tank about 7:30 pm. I had stopped running protein skimmer earlier in the day and the lawnmower blennie and the cleaner shrimp loved it so I left it off when I put everything back the way it was. I went to bed at 3:30 am and the blennie was eating away and the shrimp was on the rock moving around and the other fish were swimming around. I got up at 7:30 am (just 4 hours later) and all the fish were dead. The crabs and snails are just fine but one other weird thing is that one of the sand dollars was up out of the sand and the narsis snail was up out of the sand. They both buried themselves again within an hour and haven't seen them since. What in the world could have happened. I am totally baffled. PLEASE help me.

 

[malintner]

Did you test your water?

 

[malintner]

What was the water temperature?

 

[Merie]

yes I tested water and ph, nitrate, nitrite, and alkalinity were all in acceptable levels. water tem is 79.5 to 80.1

 

[Sk8r]

As a rule, corals and fish are not fond of change.

Did you acclimate everything? Did you quarantine everything for 4 weeks before adding to your tank?

20 baby conchs is pretty scary. Do you mean the small strombus grazers, less than 1/2 inch long?

Did you put coastal seawater into your tank [pollutants are possible], or transfer these creatures in your bare hand?

I don't know the requirements of living sand dollars, but one of them migh thave died and caused an ammonia spike. You say you have no nitrate now? What about ammonia? Acceptable levels for the nitrate and ammonia are downright 0 for some creatures. And how much do you trust your thermometer. Digital is best.

 

[Merie]

No coastal seawater put in but did keep the sand dollars and conchs (about the size of a bebe) in seawater until I got home then put them in by hand. They had been in the tank for a week before this happened and the other sand dollar might have come up in the middle of the rock as I have Univia and Bali with Tonga branch mixed in to make lots of holes with the UV light tubing going down the middle to create flow in the rock. I have been told that the sand dollars will only make it about 6 months in that warm of water which is one of the reasons I got the 10 gallon tank so that I can set them up at 72 degrees. I drip acclimate all fish for at least 2 hours before putting in my tank and have never put water in from LFS either. It was 79.5 when I went to bed and 81.1 when I got up and it is a digital thermometer. I had no nitrate then and I will check ammonia right now.

 

[Merie]

The ammonia might be high now because I can't find one of the fishes bodies. The blue chromis like to hang out in the rock towards the back. I have taken off the top layer and looked in and couldn't see him and his body has not floated to the top. ?????? on where he is.

 

[reefshadow]

Sudden overnight fish loss with no warning when they were previously doing well usually points to a drastic drop in O2 saturation. This would make sense with turning the skimmer off.

Put it back on and watch parameters, have water ready to do water changes.

Sorry that happened, it sucks.

 

[reefshadow]

Oh, forgot to add- Don't add any more fish until you are sure any cycle you are going to experience is over with.

And BTW [welcome]

 

[Merie]

Ammonia is 0.0. The other thing I forgot to say is that the girl watching the house while we were on vacation must have left the lights on alot because algae growth was phenonmenal when we got home, hence why I got the lawnmower blennie.

 

[Merie]

Why would it recycle. I had the fliter going the whole time. The only thing that got shut off was the protein skimmer. During the time I was trying to add the new tank to the system was only for about 1 hour and the filter ran for all but about 15 minutes of that. My filter and skimmer and UV run 24/7. Is that what I should be doing? I have read a lot on this forum and michigan reefkeepers but not a lot of info on how long to run things. Also I asked my girlfriend is she ever used copper in her tank and she said no. I also scrubbed her tank with just hot water for about 20 minutes before I tried the whole move thing.

 

[reefshadow]

Why would it recycle.

If you have a dead fish in there now, you may see a ammonia spike due to decay.

The only thing that got shut off was the protein skimmer.

Unfortunately this is often enough, especially overnight. Due to the process of algaes photosynthesising during the day, O2 is generally high and stable. When the lights go off and photosynthesis comes to a halt, O2 naturally drops, sometimes accompanied by a rise in CO2 and a drop in PH. A skimmer oxygenates the water with all the microbubbles in the chamber, helping to blow off CO2 and keep O2 high and stable. Basically the fish suffocate, and this can happen very very quickly (within hours), especially in relatively small water volumes. This would explain why your inverts are basically alright, they can last longer than the fish can in lower O2 situations.

The filter or powerhead you kept running probably just wasn't enough.

My filter and skimmer and UV run 24/7. Is that what I should be doing?

Definately. Keep all support equipment going at all times when you aren't actively tinkering with it. If you plan to mess around with the skimmer in the future, aim a powerhead at the water's surface to cause some agitation, break the surface tension and keep O2 up.

Also I asked my girlfriend is she ever used copper in her tank and she said no.

I wouldn't worry about this, you would have seen a massive loss of inverts almost immediately with copper contamination.

Good luck to you, sorry about the loss of your fish

 

[Merie]

Thank you for all the info. I really appreciate it. I just took all the readings again and they are ph between 7.8 and 8.0, Nitrate 0, Nitrite less than 0.2 and as I said before Ammonia 0.0. Also it has been a day and a half since this happened, do you think it would be ok to try to add a chromis tomorrow or Thursday and see if it makes it. Then go back to adding slowly again? Again thank you all for being helpful in this. My daughter and I were both devistated by this loss. It took me until the afternoon before I could even be around the tank enough to remove the dead fish. Besides my daughter wanted to help me.

 

[reefshadow]

Thank you for all the info. I really appreciate it.

Gosh, no problem, that's what we're here for. I had a similar loss early on in the hobby, I turned off the skimmer in order to collect some clownfish larvae, forgot to turn it back on and the next morning 3/4 of my fish were dead and the rest gasping on the sand. They recovered within about 10 minutes of turning the skimmer back on.

Nitrite less than 0.2

I would wait until this reads zero and you're sure you aren't going to have a spike due to some die-off you haven't seen yet.

 

[Merie]

My test kit doesn't have a 0.0 the lowest part of the scale is 0.2 and it was lighter than that color. Sorry to hear about your loss also. It is a real bummer that the fish have to pay for our stupidity. I am still looking for the blue chromis so I can get it out of there.

 

[Sk8r]

By day, plants including algae absorb co2 and give off oxygen; in the dark, they do they opposite: they absorb oxygen and give off co2---which is why fish can die at night in a heavily algaed tank.