Velvet questions

[shoelaceike]

Do you know what the max length of time it stays in the tomont stage? Also, does the parasite encase itself while on the fish or after it falls off? Meaning, when a dinospore falls off the fish, will it be killed by copper? Thanks!

 

[ichthyogeek]

Here you go, it was in the stickies:

Velvet (Amyloodinium ocellatum)

Marine Velvet Disease (Amyloodinium ocellatum) What You Need To Know: * Fast killing parasite capable of wiping out most of your fish in just a matter of days. Sometimes there are survivors, sometimes not. * Can be treated in a quarantine tank using Chloroquine phosphate or Copper. A 5...

www.reef2reef.com

 

[shoelaceike]

Here you go, it was in the stickies:

Velvet (Amyloodinium ocellatum)

Marine Velvet Disease (Amyloodinium ocellatum) What You Need To Know: * Fast killing parasite capable of wiping out most of your fish in just a matter of days. Sometimes there are survivors, sometimes not. * Can be treated in a quarantine tank using Chloroquine phosphate or Copper. A 5...

www.reef2reef.com

Thank you but I dont see an answer to either question there.

 

[kartrsu]

Fallow period for velvet is 6 weeks per HumbleFish. https://www.reef2reef.com/threads/fallow-periods-going-fishless.190324/

Considering dinospores can survive 15 days without a host, then it’s 27 days in the tomont stage or a month to be safe

From my understanding, copper works better for free swimmers as they are released from tomonts. Not effective against feeding trophonts (why FW dip, acriflavine better for immediate treatment).

 

[shoelaceike]

Fallow period for velvet is 6 weeks per HumbleFish. https://www.reef2reef.com/threads/fallow-periods-going-fishless.190324/

Considering dinospores can survive 15 days without a host, then it’s 27 days in the tomont stage or a month to be safe

From my understanding, copper works better for free swimmers as they are released from tomonts. Not effective against feeding trophonts (why FW dip, acriflavine better for immediate treatment).

Thanks. My question is when the trophonts fall off, are they susceptible to copper? The question matters if i add a fish to the medicated qt. Also, from everything I read it says that the tomont stage lasts for a max of 4 days in 22c-27c water. I just dont want to leave fish cramped in qt more than necessary.

 

[kartrsu]

I don't think trophonts are susceptible to copper. Per wikipedia, "the infusion of copper sulphate at 0.75-1 g/m3 for almost two weeks by dripping on ponds/tanks, maintaining constant copper concentration, is very effective to kill dinospores, while tomonts and trophonts are not very susceptible."

Below is from https://absolutelyfish.com/amyloodinium-ocellatum-a-k-a-oodinium-a-k-a-marine-velvet-disease/. Tomont stage can vary from 3-28 days. Where are you seeing max of 4 days? Either way, if you are targeting the "on the fish" stage, you need just several days (not sure exactly).

Anyway, to your point though, if your QT is already medicated with copper, then your existing fish will be protected from further infection since copper kills the dinospores. So if you add an infected fish, technically the existing fish can't be infected if copper is at therapeutic levels. As long as the existing fish have had enough time to allow trophonts to fall off, then they are fine. Could move them to a sterile second tank to monitor.

Hope that's helpful. I usually just go with @Humblefish recommendations.

 

[shoelaceike]

Thanks for that. I guess if I add a fish and it has velvet, I need to extend another full copper qt period. If copper doesn't kill when the theront falls off, then even with copper it will turn into a tomont and release dinospores. I saw in a study about the max tomont time in 18-30C water temperatures. I'll try to post it here.

 

[shoelaceike]

This is it.

 

[kartrsu]

Thanks for the paper. Yeah need to extend QT timeframe in copper for newly infected fish, but existing fish theoretically can be removed earlier if you are certain trophonts have fallen off because 1) they are protected by copper so can't be reinfected, 2) and will have no more feeding parasites on them. But best to monitor in a transition tank before adding to display.

 

[shoelaceike]

Thanks for the paper. Yeah need to extend QT timeframe in copper for newly infected fish, but existing fish theoretically can be removed earlier if you are certain trophonts have fallen off because 1) they are protected by copper so can't be reinfected, 2) and will have no more feeding parasites on them. But best to monitor in a transition tank before adding to display.

Thats true. Thanks. Did you see about the tomont stage?