Low levels of Cu masking crypt/velvet?

[Deinonych]

So, I hear every so often that many LFS run copper below therapeutic levels, and that this can mask symptoms of cryptocaryon and amyloodinium. Can someone explain how this happens? I was under the impression that Cu+ concentration in solution below a certain threshold is completely ineffective, but I don't have a basis for that assumption.

Any thoughts from the experts here?

 

[snorvich]

Not cryptocaryon irritans, but it does mask amyloodinium. I have seen it happen many times. However I have not researched the "why" issue.

 

[Deinonych]

Thanks. I wonder if low levels kill off some (but not all) of the theronts so that fish can have a subclinical infection?

 

[snorvich]

Thanks. I wonder if low levels kill off some (but not all) of the theronts so that fish can have a subclinical infection?

I have speculated about why this is and at this point I do not want to pass on speculations. I do know that some of the sources were also using UV in their system. It is also interesting that there seem to be some generalized species (butterfly fish) that seem more predisposed.

It may also be true of brook but I have insufficient data points on this; most folks that have fish that contract brook do not know if their source had a low level of copper in their system.

 

[rog2961]

my LFS did this with it's trigger, ich within a week.

 

[snorvich]

my LFS did this with it's trigger, ich within a week.

Unrelated. LFS systems share water among tanks so ich is passed quickly to all fish which may or may not show visible symptoms. However, the fish likely had ich coming in.

If this were the situation being discussed, the trigger would NOT have evidenced ich. The situation being discussed with low level of copper in LFS systems is that fish do not show velvet (Amyloodinium ocellatum) until they go to the customer tank. That is, low levels of copper mask the parasite.

 

[Deinonych]

Thanks Steve for your thoughts on this.

 

[Newsmyrna80]

This was the case of a yellow tang I had in a QT earlier this year. I had him in a QT for 3 weeks with no meds. He was eating great, looked good and then he was gone within 12 hours. The LFS ran low levels of copper in their system. I would have thought that velvet would have shown itself within 3 weeks. I dosed CP but I lost the fish anyway.

 

[snorvich]

This was the case of a yellow tang I had in a QT earlier this year. I had him in a QT for 3 weeks with no meds. He was eating great, looked good and then he was gone within 12 hours. The LFS ran low levels of copper in their system. I would have thought that velvet would have shown itself within 3 weeks. I dosed CP but I lost the fish anyway.

No. And if you think about that three week interval you will start to understand where my speculations point.

 

[Deinonych]

This was the case of a yellow tang I had in a QT earlier this year. I had him in a QT for 3 weeks with no meds. He was eating great, looked good and then he was gone within 12 hours. The LFS ran low levels of copper in their system. I would have thought that velvet would have shown itself within 3 weeks. I dosed CP but I lost the fish anyway.

Yikes. Makes me rethink my CP dosing schedule. I usually start CP after two rounds of prazi. Maybe I should start it after the first round.

 

[Newsmyrna80]

Yikes. Makes me rethink my CP dosing schedule. I usually start CP after two rounds of prazi. Maybe I should start it after the first round.

I think the CP I had was not pure. I got it from a supplier (don't want to say who) but I've read others have had the same experience. I know of others that had success using CP to treat active velvet

 

[Newsmyrna80]

No. And if you think about that three week interval you will start to understand where my speculations point.

Geez, that's scary. I know it's speculative but how can a fish be asymptomatic for 3 weeks? All the more reason to QT for a couple of months. I now quarantine corals and LR for 8 weeks:spin2:

 

[snorvich]

Geez, that's scary. I know it's speculative but how can a fish be asymptomatic for 3 weeks? All the more reason to QT for a couple of months. I now quarantine corals and LR for 8 weeks:spin2:

visible symptoms are never immediate in velvet or especially cryptocaryon irritans. The first symptoms are usually behavioral.

 

[Deinonych]

Geez, that's scary. I know it's speculative but how can a fish be asymptomatic for 3 weeks? All the more reason to QT for a couple of months. I now quarantine corals and LR for 8 weeks:spin2:

+1

I got burned by not quarantining corals. Never again.

 

[SDguy]

Not cryptocaryon irritans,

How would you determine if it's the low level "masking it", or simply the fish being a carrier (ie even with no copper there would be no symtoms)?

 

[Mrscribbled]

After not dealing with velvet for 6 years, I just dealt with it this past weekend. Had all the fish for 3 weeks. Was raising copper up for treatment, then bam! All were taken by velvet in a matter of 14 hours... never saw it coming. All in all it was a learning experience in symptoms and refreshed my already full mind on the disease.

 

[snorvich]

How would you determine if it's the low level "masking it", or simply the fish being a carrier (ie even with no copper there would be no symtoms)?

What I know for a fact is that the fish came from a reputable dealer (some locally, some nationally) that had a non-therapeutic dose running in their system, and in the case of the national supplier, also UV. Given the length of time in the supplier system (7 weeks), it would seem that this masked the parasite incidence in the supplier system. But of course, the fish was carrying the parasite and developed symptoms almost exactly three weeks after arrival. By the way, I was not the only one that had this experience. Total fish I have seen this in so far is 8 (or maybe ten?) over about 5 years that I have been tracking it. All but two were from a national supplier that runs copper and UV.

 

[snorvich]

After not dealing with velvet for 6 years, I just dealt with it this past weekend. Had all the fish for 3 weeks. Was raising copper up for treatment, then bam! All were taken by velvet in a matter of 14 hours... never saw it coming. All in all it was a learning experience in symptoms and refreshed my already full mind on the disease.

What I find interesting, anecdotally, is it seems as if the interval before developing it after arrival seems to always be 3 weeks.

 

[Deinonych]

What I find interesting, anecdotally, is it seems as if the interval before developing it after arrival seems to always be 3 weeks.

This is good information to go on, even if it's only anecdotal. I typically start prophylactic treatment with CP ~2 weeks after introduction into QT, so this would catch it in time.

 

[snorvich]

It is a strange issue since the lifecycle of the parasite would normally exhibit symptoms more quickly than these fish have shown them. But I hate using anecdotal evidence to establish causality. Or at least not without a statistical basis.