Hypo-salinity killing my fish??

[bguile]

My preferred method of medication when it comes to ich is to use hypo-salinity as I have read that using copper has other adverse affects on certain fish such as decreased immune system, etc. However, I have lost 4 of my last fish during the hypo cycle. It always happens the same way. The fish is alive and moving fine one day, the next morning...dead. They all look the same too...whitish, like they saw a ghost or something. I have lost 3 tangs and a coral beauty.

My parameters have been the same, reduce salinity over 3 days from 1.026 to 1.009. I am using a refractometer for precise salinity measurement. Tank temp is constant at 80deg F. No ammonia. I check pH which stays around 7.9.

As in the last case, I purchased the beauty and brought it home and acclimated for the QT. After a few days of observance, I saw the fish flashing so I removed the liverock that was in the tank (which came from the sump of my display) and began to lower the salinity. 1.009 was reached 2 weeks ago. I have kept it steady there until 3 days ago when I started to bring it back up. However, I arrived home on yesterday to find the fish dead. Is there something I'm missing or doing wrong?

[Reefland]

Are you doing this in the display tank? If so the hyposaline water has probably killed all necessary bacteria and the result may be toxic levels of ammonia?

[michael7979]

How big of a tank is the QT?

If you are using a 10 or 20 and dropping the salinity from 1.026 to 1.009 in three days thats a very fast drop and will surely shock the fish even more.

[bguile]

Are you doing this in the display tank? If so the hyposaline water has probably killed all necessary bacteria and the result may be toxic levels of ammonia?

No. This is in a QT of 10 Gallons. I still have some of the water that was in the tank just before the fish died so I'll test that for ammonia levels. I had the LR in the tank for about a week and a half to help keep ammonia down until the bacteria could be developed in the filter and it tested undetectable well after the salinity drop but I'll check it out.

[ldrhawke]

No. This is in a QT of 10 Gallons. I still have some of the water that was in the tank just before the fish died so I'll test that for ammonia levels. I had the LR in the tank for about a week and a half to help keep ammonia down until the bacteria could be developed in the filter and it tested undetectable well after the salinity drop but I'll check it out.

If you are using a QT the fish are probably easy to capture. Why don't you simply do a 3 to 4 minute dip in fresh water. I recently obtained a new copperband and he was covered with ich within a few days after I got him home. A quick 4 minute fresh water dip and within 24 hours there is no sign of the ich. If it reappears over the next two weeks I'll simply dip him again.

It may be a little more stress on the fish for a few minutes, but it allows for plenty of recovery time, and probably less stress overall.

[joecon]

Why don't you simply do a 3 to 4 minute dip in fresh water. If it reappears over the next two weeks I'll simply dip him again.

It may be a little more stress on the fish for a few minutes, but it allows for plenty of recovery time, and probably less stress overall.

So you can put a saltwater in 100% freshwater for a few minutes? The fish can live THAT long in FW and won't kill the fish? I understand there will be major stress on this fish, but I had no idea they can survive in FW for a few minutes. Interesting and thanks for sharing.

Joe

[Triggers]

I have kept it steady there until 3 days ago when I started to bring it back up. However, I arrived home on yesterday to find the fish dead. Is there something I'm missing or doing wrong?

that is most likely the issue right there..fish can adapt much easier to rapid drops in sg but can stress badly if it rises to quickly.

page 7 on my thread below will give a link to proper procedure for safely raising sg.

http://reefcentral.com/forums/showth...hreadid=595224

[bguile]

Well, I've tested the water and came up with practically no ammonia. Got a reading of ~.025 which I normally get from my display also. I have never gotten a crystal clear reading, especially seeing that one of the agents in my test is yellow.. Anyways, pH also tested at 7.9 so I'm not sure what the problem is.

Thanks for the extra link Triggers. I had only begun to raise the SG which was only moved from 1.009 to 1.012 in 3 days. So I'm doubting its a shock in raising the SG unless there's something I'm missing.