Purple tang in QT looking bad

[Greenjeans]

I've had this purple tang in QT for about a week. It's been active and eating up until today, when I noticed it swimming/struggling at the bottom of the tank, listing on its side, etc.

it was in 1.017 salinity water and 0.25 copper at the fish store

My QT is at 1.015, and I increased the cupramine dose to the recommended 0.50 (checked with a hanna) the day before yesterday, along with adding a dose of prazipro.

The tank is a 20gal long with a sponge filter and rocks that had been in my sump for several months. Hob filter (only sponge media) at one end and a powerhead at the other.

I'm worried that either the salinity is too low, the copper is too high, the prazi is too much, or a combination of all three of these things.

What do I do? I'm considering a water change with 1.015 water without copper/prazi, to reduce the concentration of those things...

 

[Big G]

The lower the salinity the higher the toxicity of the copper. Treating with copper below 1.017 is not advised.

 

[Greenjeans]

Okay, so should I do a water change with higher salinity water? I was following the fish store guy's advice re: copper and salinity

 

[Bpfor3]

Agreed, don't need lower salinity and copper. I would do a water change with same salinity and no copper. When he recovers, slowly raise the salinity and then slowly raise the copper to correct levels. good luck!

 

[Miller535]

The lower the salinity the higher the toxicity of the copper. Treating with copper below 1.017 is not advised.

Wow. I did not know this. What salinity do you usually use to treat with copper?

 

[Greenjeans]

I just did a 20% WC with the same salinity and no copper. I'll do it again a few a times maybe 30 minutes apart?

If it stabilizes, I'll start slowly increasing the salinity.

 

[Miller535]

I just did a 20% WC with the same salinity and no copper. I'll do it again a few a times maybe 30 minutes apart?

If it stabilizes, I'll start slowly increasing the salinity.

Unless you already have a bunch of saltwater mixed up, I would not do this. As it takes at least a few hours for freshly mixed saltwater to fully mix and dissolve. Otherwise you can burn their gills. Which in your case is just making the situation worse. If you already did a water change, maybe mix up another batch and later in the afternoon early evening do another. Then I wouldn't do any more today.

 

[Greenjeans]

I have 75gal on hand, mixed up last week

lol, I might actually end up running out of my RODI on hand from diluting it down to 1.015

 

[Bpfor3]

i use copper guard, but its 1.025-1.026, same as DT.

 

[Miller535]

I have 75gal on hand, mixed up last week

lol, I might actually end up running out of my RODI on hand from diluting it down to 1.015

I still wouldn't do too many. Do another one in a little bit, and put some carbon in if you have it. That'll absorb some of the copper as well.

 

[Greenjeans]

I've done two 20% water changes...I'll add carbon and wait.

 

[TriggerFinger]

If you have another cycled QT that matches the salinity, another option is to transfer the tang to that tank and start over with copper at a higher salinity.

 

[Greenjeans]

I have a coral QT tank that matches the salinity of my DT, so unfortunately too high for this fish.

I've done one more 20% water change, for a total of 3x 20% changes. That should bring my copper down from .5 to .25, which is where it was when the fish was doing fine. I've added carbon as well.

The fish is still alive, but just barely

When should I start increasing the salinity? I could do it by changing out one scoop at a time with fresh salt water over several hours...?

 

[Big G]

I could do it by changing out one scoop at a time with fresh salt water over several hours...?

This ^^^ exactly. Small steps. Going up in salinity is hard on many fish's organs.

 

[Greenjeans]

The fish died This is difficult and frustrating...I guess I learned a lesson about salinity+copper.

 

[Bpfor3]

i wouldn't do anything else the rest of the day. messing with the tank = more stress. if he makes it through the night then you can increase salinity sloooooooowllly.

 

[Miller535]

The fish died This is difficult and frustrating...I guess I learned a lesson about salinity+copper.

I'm sorry. I have lost a few fish in QT myself. It is very frustrating and deflating. But you learned something for the next time. I would also suggest next time using copper power instead of cupramine. Copper power is supposed to be easier on the fish, and I have had better luck with it.

 

[Greenjeans]

Thanks.
So my new QT plan is then:
- Set up QT @ 1.026, 77-78F, cycled
- Drip acclimate/introduce fish
- Observe ~3days for eating/behavior
- Use copper power and PraziPro
- Use only one 7-day round of prazi unless ongoing indicators of parasites
- Observe for 30 days

I do have one question - I had a foxface that made it through a QT (from LiveAquaria Diver's den) and 30 day observation, but then got intestinal worms. Should I feed medicated food while in QT as well, or rely on the Prazi in the water to do that?

 

[Bpfor3]

The fish died This is difficult and frustrating...I guess I learned a lesson about salinity+copper.

oh man. i feel your pain. putting all that effort in trying to do it right and having it not work out is frustrating. you know what is more frustrating? have a non-QT'd fish crash your display tank. just keep at it. there are some really good articles by humble fish and others on this forum about QTing fish.

 

[Bpfor3]

Thanks.
So my new QT plan is then:
- Set up QT @ 1.026, 77-78F, cycled
- Drip acclimate/introduce fish
- Observe ~3days for eating/behavior
- Use copper power and PraziPro
- Use only one 7-day round of prazi unless ongoing indicators of parasites
- Observe for 30 days

I do have one question - I had a foxface that made it through a QT (from LiveAquaria Diver's den) and 30 day observation, but then got intestinal worms. Should I feed medicated food while in QT as well, or rely on the Prazi in the water to do that?

i believe metro soaked food will get the intestinal worms. i would also use two rounds of prazi about 7 days apart. prazi usually makes my fish quit eating, but you only need it in the water for 24 hours for it to work. good luck!