1 fish, 2 fish, dead fish!

[NuraNori]

So where do I begin...

I've had ich on and off in my 75G tank since I have inherited it. Since I occasionally loose a new fish to ich and the 6 residents will get ich from time to time, I decided to take it upon myself to irradicate ich in my DT.

Since I had a 40 Gallon tank I decided to try the hyposalinity treatment and leave my DT fishless for 6-8 weeks. This was after some extensive reading on the subject and thought I had it down.

So I set up the 40 gallon with a powerhead, heater and some PVC pieces for hiding places. Had the salinity at 1.013, nitrates undectable, nitrites 0 and ammonia 0. The pH was buffered to 8.3 and the temp was consistent with the DT.

I then thought I was ready to rock and went fishing!! So I spent most of last night catching 2 out of the 6 fish and placed them into the 40 gallon tank. They seemed happy swimming around last night. When checked this morning they were still doing well (swimming around actively) and off to work I went. I came home this afternoon (4pm) to a dead Damsel and a trigger that was breathing quite rapidly. The trigger was still swimming around and seemed to be coping.

I then checked the parameters and the only one showing anything out of the ordinary was the ammonia 0.25. So I prepared myself for a water change and the trigger started to deteriorate rapidly. By the time I got things organized for the water change it was dead.

So I am now frustrated and still want to get the ich out of my DT. I want to know where I went wrong and what I can do to avoid this happening again.

....

[ferret]

I think you're doing too fast by catching the fish from the display tank and transfered to the 40gal tank right away. To me, if switching from salinity from
1.022 to 1.013 will require 2 to 3 days particularly for the sick fishes. HTH

[NuraNori]

If this was the case that it was Salinity shock would they not have perished within a half hour or so? They looked fine last night and this morning. Can it take a day for the salinity to shock them. I know when you go from a low salinity to higher salinity you must acclimate them slowly. But as far as I read going in the opposite direction should have no effect on them.

[BlueTang<3]

were they acclimated to that water or just thrown in

usually with a hospital tank you wanna use you dt water

[NuraNori]

Here is the link to the instructions I was using

http://www.reeftime.com/reef-article...salinty/19.htm


I was using my tank water. I just added RO water to bring the salinity down.

[PoonTang]

you should use dt water in your qt and then slowly lower the salinity over a few days. you are still going to have to deal with the ammonia tho.

[NuraNori]

well we are going to trod on with the process.... We have now done a large 50% water change and ammonia is down to zero and we have now brought the salinity up to match the DT so we are waiting for the temperature to match the DT and then we will try adding the other fish and see how it goes. Once all the fish are in the tank and doing well we will bring the salinity down slowly to 1.012.

Hopefully this was where the mistake was made.

Thanks

[fishoholic]

The biggest thing I found with QT tanks (I've lost a few fish to ammonia spikes in QT tanks in the past when I thought doing large weekly water changes was good enough) was that you have to do a 40 to 50% water change every 2-3 days. Which BTW really sucks when you have a 110g QT tank running. I used more salt in the 2 months of QT'ing my fish (when they had marine velvet) then I usually use in about 5 months. However it was the only way I found I could keep the ammonia and nitrite levels in check.

I agree it is best to bring salinity down slowly but it is very important to raise the salinity at a very slow rate. When you're ready it should take about 2 weeks to slowly raise the salinity back up.

[cuz]

just a curious question nora.. but where have you been purchasing your fish? There has been a lfs in lethbridge that has been causing grief for alot of people. (granted proper QT may not have been met) The lfs themselves admitted that their entire last order may have fallen to marine velvet!!