Ich, velvet.... time till symptoms?

BoneXriffic · Aug 3, 2016

If a fish is introduced into a tank with velvet or ich, whats the lengh of time it would take for a fish to be infected? And show signs? Lets base this in a tang, cliwns i understand can take longer. I am working on a write up and any info is helpful. Would the fish coming from a tank with cupramine take longer to be afflicted?

Deinonych · Aug 3, 2016

Velvet kills quickly; typically a matter of a few days. Crypto infections are more protracted. Fish could be infected for weeks without showing visible symptoms.

Amyloodinium ocellatum (marine velvet) primer
Cryptocaryon irritans (marine ich) primer

BoneXriffic · Aug 3, 2016

Deinonych said:
Velvet kills quickly; typically a matter of a few days. Crypto infections are more protracted. Fish could be infected for weeks without showing visible symptoms.

Amyloodinium ocellatum (marine velvet) primer
Cryptocaryon irritans (marine ich) primer

Thanks for this, this is good news for my little experiment actually.

4FordFamily · Aug 3, 2016

I've actually seen velvet run dormant for weeks, I've also seen where fish didn't show any outward symptoms (spots or dusting) just cryptic behavior and then abruptly stopped eating, then dying -- where it ended up being velvet. Fish kept dropping for a couple months each time I thought I identified the culprit until a chevron tang finally displayed outward spots and classic symptoms (swimming in powerhead). Copper fixed it all. Long story short my existing fish were very resistant (mostly wrasse) even a hippo tang. Eventually a few days before the chevron showed symptoms the hippo succumbed. The wrasse never showed any symptoms. My angels dropped dead in 2-4 days from addition.

Ich can "hide" for a month or more before being noticeable. I've seen this as well.

Typically velvet has a delay of 2 weeks or so if the fish came from low levels of copper (which is most LFS these days). Ich I suspect may follow similar patterns but that cannot be confirmed that I know of.

@Humblefish may have something to add or correct me on

Humblefish · Aug 3, 2016

This is a difficult question to answer because a lot depends upon the species of fish. I would expect an Acanthurus Tang (especially a PBT or Achilles) to show symptoms of velvet within days and die in a week or less. But it could be considerably longer for a thick slime coat species, such as a wrasse or clownfish. I've actually seen clownfish survive for months following a velvet wipe-out (left untreated), and the only logical explanation for that is they were able to build up natural immunity of some sort. :confused:

Ich is a whole different ballgame, as many fish can cope with that parasite almost indefinitely and/or it can harbor inside the gills sight unseen. An Acanthurus Tang (again, especially a PBT or Achilles) is one of the few fish I can guarantee you will eventually see white dots on the skin. With many others, you may only see behavioral symptoms of Crypto.

BoneXriffic · Aug 3, 2016

Humblefish said:
This is a difficult question to answer because a lot depends upon the species of fish. I would expect an Acanthurus Tang (especially a PBT or Achilles) to show symptoms of velvet within days and die in a week or less. But it could be considerably longer for a thick slime coat species, such as a wrasse or clownfish. I've actually seen clownfish survive for months following a velvet wipe-out (left untreated), and the only logical explanation for that is they were able to build up natural immunity of some sort. :confused:

Ich is a whole different ballgame, as many fish can cope with that parasite almost indefinitely and/or it can harbor inside the gills sight unseen. An Acanthurus Tang (again, especially a PBT or Achilles) is one of the few fish I can guarantee you will eventually see white dots on the skin. With many others, you may only see behavioral symptoms of Crypto.

Velvet was the likley killer. And i had a clown and damsel survive and have become healthy as can be.

I had a theory that i, as a side effect, killed off the velvet from my tank. Yes unlikley I know. But plausable. Im a bit confident as well. I purchased a blue hippo. They tend to be pretty intolerant of velvet if i am not mistaken. 5 days now and still disease free. My write up will come soon. But my theory is atleast floating for the time being.

Humblefish · Aug 3, 2016

BoneXriffic said:
Velvet was the likley killer. And i had a clown and damsel survive and have become healthy as can be.

I had a theory that i, as a side effect, killed off the velvet from my tank. Yes unlikley I know. But plausable. Im a bit confident as well. I purchased a blue hippo. They tend to be pretty intolerant of velvet if i am not mistaken. 5 days now and still disease free. My write up will come soon. But my theory is atleast floating for the time being.

You could also put a FW black molly in there to test: https://www.reef2reef.com/threads/fallow-periods-going-fishless.190324/page-2#post-2855190

Doesn't always work for ich (due to the unpredictability of the backend life cycle), but will almost certainly work to confirm velvet.

BoneXriffic · Aug 4, 2016

Fantastic idea, thank you

4FordFamily · Aug 4, 2016

Watch the hippo closely as it can drop without outward symptoms. Any behavioral change at all should result in removal and treatment.

Hippo tangs can develop strong immunities and quickly, 1/2 do this IME. The other half die quickly.

If you bought the hippo from another hobbyist or the store had it awhile before you got it, it may already be somewhat resistant. In the end if velvet is present, that fish is done for if not removed eventually. Whether that's days or months. My hippo lived in velvet for 2-3 months before succombing. (I didn't know what disease it was since I never saw spots during that timeframe).

If you discovered something that could eradicate velvet, do share. I will tell you that fresh water doesn't do it (unless for long periods), nor does high or low temperature, praziquantel, reduced light, etc.

Humblefish · Aug 4, 2016

If you wanna experiment with velvet, here's one I'd like to try:

Formalin concentrations as low as 25 mg/L, a common therapeutic dose, cause trophonts to fall off of parasitized fish within a few hours (Paperna, 1984b).

Source: http://agrilife.org/fisheries/files...mportant-Parasite-of-Cultured-Marine-Fish.pdf

I'm not a big fan of using formalin, but if a 3 hr bath is capable of eradicating velvet on a fish... I think that's a weapon everyone would like to have in their arsenal. ;) Of course, it is unclear if a "few hours" of exposure time is enough for complete eradication or just temporary relief. o_O

The question is: Does a 3 hr formalin bath @ 25 mg/L dislodge all of the trophonts, or just some/most of them? You'd have to place the fish in a non-medicated sterile QT, post bath, to see whether or not symptoms return. You could probably dose Kanaplex to help with any potential secondary bacterial infection.

BoneXriffic · Aug 4, 2016

Humblefish said:
If you wanna experiment with velvet, here's one I'd like to try:

Source: http://agrilife.org/fisheries/files...mportant-Parasite-of-Cultured-Marine-Fish.pdf

I'm not a big fan of using formalin, but if a 3 hr bath is capable of eradicating velvet on a fish... I think that's a weapon everyone would like to have in their arsenal. ;) Of course, it is unclear if a "few hours" of exposure time is enough for complete eradication or just temporary relief. o_O

The question is: Does a 3 hr formalin bath @ 25 mg/L dislodge all of the trophonts, or just some/most of them? You'd have to place the fish in a non-medicated sterile QT, post bath, to see whether or not symptoms return. You could probably dose Kanaplex to help with any potential secondary bacterial infection.