Visibility of Parasites on Fish Gills

[Overboard]

Hi,

I had a fish die in quarantine without any apparent outward signs of parasites. He was fine last night, but this morning was breathing very rapidly. Died 3 hours later. If the fish had ich or velvet on the gills, would that be visible under a magnifying glass? I examined the gills and I could not see any spots as with ich as might be visible on the fishes extererior. Not as good as a microscope, but the magnification and lighting were good and I could see the details of the gills well. Did not see any obvious issues. Just curious if the parasites on the gills would be visible.

Thanks!

 

[deedubz]

Unfortunately most parasites are far too small to see.

Depending on the fish, that timeframe of decline coupled with a lack of outwards signs leads me to believe you're likely dealing with velvet. Is there any survivors still in the qt? If so, I'd start ramping up copper (which will also treat ich)

 

[deedubz]

Here's @Humblefish procedure for copper. If you do have others you may also want to consider the emergency protocol outlined in post 2

https://www.reef2reef.com/threads/velvet-amyloodinium-ocellatum.217570/

 

[Overboard]

Thanks for your assistance dwwataz.

Fish have been in QT for a week with CP (the good stuff) at 40 mg/gallon. Monitoring ammonia closely with badge and Seachem test kit. No indication of ammonia but did a 63% water change last night as it had been a couple of days, (slowly) matching temperature and such. An emperor and Achilles tang are still doing fine. With the water change, I raised the CP level to about 50 mg/gallon as I thought I was seeing just the very early stage of ich on the Emperor. The fish that died was a Tinker and I suspect sensitivity to the higher level of CP. That is the only factor that changed. I guess I can’t rule out velvet completely though, so I will watch the other guys closely. The Tinker was eating like a pig, even during the water change so the CP level seems a potential cause. On the chart that is part of a sticky thread up above, butterflies are marked as “1” for CP, but not specifically Tinkers. Might be this subgenus has greater sensitivity. All speculation, of course.

Been using the Seachem digital spoon, so might look for a higher quality scale too.

 

[Josh Kraft]

Just to double check, when you do water changes, do you dose the new water with the equivalent of your current dose? From the looks of things, you have a handle on everything, but just want to double check.

 

[deedubz]

Just to double check, when you do water changes, do you dose the new water with the equivalent of your current dose? From the looks of things, you have a handle on everything, but just want to double check.

Exactly what I was going to ask. Sounds like everything else is going well

 

[Overboard]

Hi JK, I appreciate the question!

Yes, I dosed the replacement water prior to the water change to be sure the concentration level never fell below the prescribed level.

The thought of velvet is unsettling, to say the least. I will feel better when I get home this evening and can check out the angel and tang. As much as I hate to lose a fish for any reason, I would at least take some comfort if I am learning about CP sensitivity in Tinkers. It might also be this particular fish was simply more sensitive to the medication than others. Thinking this through, other non-velvet possibilities would be (1) a sudden spike in ammonia (will check this evening) despite the water change and stability over the last week, or (2) water contamination from another source (use a brute trash can to mix fresh saltwater).

Now that I think of it, I have not used that particular can in several weeks. I moved water from my garage mixing station to my utility room, into this can, to let it cool some (getting hot here). It possible something got in the can without my knowledge as it was stored elsewhere in the garage. Hope not. I rinsed it out before using it. Did not see signs of stress in the other fish around noon.

 

[Humblefish]

When a fish dies under mysterious circumstances, you have a few options:

1. Drop the body into freshwater to see if any flukes come off.
2. Take a gill biopsy and look for parasites under a microscope.
3. Perform a necropsy and examine the condition of the fish's internal organs.

I've been doing all 3 whenever a fish dies, and have been finding a disproportionate number of fish with damaged livers.

 

[Josh Kraft]

When a fish dies under mysterious circumstances, you have a few options:

1. Drop the body into freshwater to see if any flukes come off.
2. Take a gill biopsy and look for parasites under a microscope.
3. Perform a necropsy and examine the condition of the fish's internal organs.

I've been doing all 3 whenever a fish dies, and have been finding a disproportionate number of fish with damaged livers.

Any chance you document and can share what certain things look like? Including parasites or damaged organs with pictures?

 

[Humblefish]

Any chance you document and can share what certain things look like? Including parasites or damaged organs with pictures?

I've been storing the photos on a flash drive. Just gotta find the time to write up an article.

 

[Overboard]

That would be very helpful Humblefish! I need to breakdown and get a microscope and learn a little biology. (Wanted to be a marine biologist as a kid, then realized I needed to pay rent, buy a car, get married.....!).

Did not think of the FW dip. Good idea. Making journal notes.

On the encouraging side, I am happy to say the angel and tang are acting normal and eating ravenously.

Thanks guys!