Is there any way to fix the monster I created?

[mikebern]

I am at my wits end. I have a 265 gallon FOWLR and started the tank March 2008. Had about 15 small fisn (yellow tang, cardinals, etc) up until December. I added 3 fish that were not quaranteened (I know already this was a bad thing to do). 30 minutes after the fish were added, the bigger fish all died lying on their sides and the small fish were all gasping for air at the top of the tank. All fish were dead within 24 hours. Ammo and nitrates were 0 but nitrates were 80. Over the next two weeks I systematically changed over half the water. When all readings for the water were safe, I added 7 more fish (tang, blenny, small angel, etc). Within 3 weeks all these fish were dead. They died one at a time with no apparent signs of aggression or disease. I left the tank running empty (except for the rock and some inveersts) for 5 weeks. I added a yellow tang, a small lion and blenny this past Saturday. The lion and blenny died in 2 days and now the tang is flashing. The water parameters are normal and no apparent signs of disease on any fish. Besides not using a Q tank, can anyone tell me what is going on here and why I cannot keep any fish alive in this tank? Better yet, how can I fix this? Please, please help. Any help is appreciated.

 

[queenangel77]

Very sorry to here about your losses. How is your tank heated. Your fish are not getiing shocked are they? I have heard of that happening before. What is your temp? does is very threwout the day? any big salinity changes?

 

[Bifferwine]

I think if anything, your problem has been adding too many fish at once. Even in a larger tank, you shouldn't add more than 1 new fish every 3 weeks or so. If you add 5 or 7 fish at a time, your systems is going to go into shock. Your bacterial bioload just can't keep up with that sort of stress.

 

[yote]

Also,what exactly is your salinity? and are you test it with a hydrometer or refractometer?

 

[mikebern]

I test the salinity about once a week. It has never gone over 1.25 but does swing between 1.23 and 1.25 over a few weeks time. It raises a little with evap but I lower it back when I perform water changes (every two weeks about 10%). I regularly test with a hydrometer. I have a refractometer but do not use too often. The temp. is around 80 degrees and does not flux much. I am going to add a probe tonight hopefully to eiliminate any stray elect. flowing in the tank. The advice so far is very helpful. I am curious to know if anyone thinks I have to throw everything out and start all over. That would be very costly. All the fish that have died have also cost a pretty penny. Again I want to thank everyone for thier advice and welcome any more.

 

[daugherty]

no you should not have to throw everything out you just need to let the tank get healthy for now by not adding anything to it and then when you want to add fish do it one at a time unless it is a pair of something then dont add anything for a couple weeks than add again

 

[yote]

Make sure your refractometer is calibrated and start using it to check the salinity.For now anyway,untill we get your problem figured out.
I'm inclined to think its either the salinity OR stray voltage.Theres an article here somewhere about the how to check for the voltage,but I cant remember the link.

 

[mikebern]

Okay, thanks. I think I will let it sit for another month with the one fish in it and start again slowly. Thanks for your help.

 

[Teixeira29]

Has your aquarium been cycled? It could also be your salinity could be going up and down. I think that your just putting to much fish in there at once and your system is in shock! What kind of filtration are you running?

 

[mikebern]

The first time I had losses in December, I had the tank running for 9 months and never lost a fish in that time. I changed a lot of water since first to lower the nitratres and also thinking there was something I had to flush out. When I added the 3 fish this last Saturday, I had the tank running for 5 weeks with weeking testing. All the paramenters looked good except for the salinty raising slightly.

I am currently running a Fluval FX5. Thanks for your help.

 

[ccCapt]

What is your nitrate reading now? You said you systematically changed 50%. Was it 2 25% changes? That would take you from 80 to 60 and another 25% would drop it to 45. Putting new fish in a high nitrate level tank can kill them pretty quickly. Fish can gradually get used to higher nitrates, but the shock from low to high can kill fast.

 

[Bifferwine]

Here is the article about stray voltage that I reference all the time:
http://saltaquarium.about.com/od/aquariummaintenancecare/a/aastrayvoltage.htm

Also, I think it's very rarely so bad that it's necessary to throw everything out and start all over again. In your case, it doesn't seem like salinity and temps are problems, so if you eliminate stray voltage as a cause and only add fish very slowly, let's see how things go instead of deciding to throw in the towel at this point in time.

 

[Bifferwine]

Here is the article about stray voltage that I reference all the time:
http://saltaquarium.about.com/od/aquariummaintenancecare/a/aastrayvoltage.htm

Also, I think it's very rarely so bad that it's necessary to throw everything out and start all over again. In your case, it doesn't seem like salinity and temps are problems, so if you eliminate stray voltage as a cause and only add fish very slowly, let's see how things go instead of deciding to throw in the towel at this point in time.

 

[mikebern]

I changed water slowly over a few weeks, a little evey couple days since it ways empty. The nitrates are now around 15-20.

Thanks for the article. I am going to buy a voltage meter in about an hour and and a probe to the tank regardless of the meter reading.

Thanks for your advice. I am regainging some confidence and hope I can save this thing.