[DanG]

In my heavily planted 29 gallon tank a couple of the Cardinal Tetras has shown symptoms of lymphocystis. I am fairly certain I've diagnosed this correctly, as it is pretty distinct from other diseases. Prior to this, it appeared on a cory. Fish have acted normally, though a couple have disappeared (there was a healthy shoal, and as I said, the tank is heavily planted). Water quality and maintenance are excellent. Fish were quarantined for at least a month before introduction to the tank without symptoms. I have seen on one fish earlier, and it seems to be self limiting. But it can get severe enough to affect the fish's ability to thrive (and may have accounted for the disappearance of a fish or two). So...

Apparently this is a viral disease that can persist in the water column. I am considering getting an Aqua Ultraviolet Advantage UV Sterilizer Hanger Unit, maybe 8 watt, with an appropriate pump (may need help selecting this), if it can be effective eliminating this virus from the tank. Love to get thoughts. Worth posting this in the equipment forum?

 

[ichthyogeek]

Hmmm...I'm not super experienced with UV filters, but I think that if you're trying to kill viral particles, you should get an oversized one. As you're probably aware, it's really, really hard to kill a virus.

Lympho kinda just hangs around on fish. Think of it as the cold sore equivalent. Fish can get it. Most of the time they can deal with it. Sometimes they don't, and then the virus kinda just takes hold.

Most treatments for lympho involve doing water changes and feeding the fish better quality food. If it's showing up on fish, then that might mean that something about the water is "off" to them.

 

[DanG]

Well, I've ordered it, but wonder if I undersized it now. I called Aqua Ultraviloet to get their advice directly. They said a 15 watt would be way oversized for a 29 gallon freshwater tank, and the 8 watt would be better. Their 8 watt is rated for 5-200 gallons, the 15 watt for 200- 500 gallons. I mentioned wanting Level 1, to "control" viruses. He kind of dissed the whole "Level" idea.

Also got their advice on flow gph minimum and maximum. So I picked a pump within those parameters on the lower end to increase dwell time. It still has a very high turnover rate. I hope it does the trick. I will decide whether to run 24/7 (their recommendation) or when lights are off because of the effect on the iron fertilizer. Will go to a daily iron dosing regimen first thing. Another thing about the Aqua UV: they recommend changing the bulb after 14 months of continuous use, as opposed to 6 months, which one sees with many other brands.

On the disease topic, one large Cory has a large white growth behind a pectoral fin. This has been present for many, many weeks (months?). It is large, kind of round, and smooth. The Cory seems to show no ill effects (knock wood) from it. I wonder if it is similar to what has affected a couple of the tetras. Another Cory had a similar affliction "absorbing" 'the caudal fin (might have been the source) but it has been long gone.

 

[ichthyogeek]

If your goal is to reduce viral load, then you need to be running that light 24/7. Viruses don't sleep.

It sounds like lympho. What's your water change schedule? Your feeding schedule?

 

[DanG]

Thank you for the good advice. I do a water change once a week, about 35 - 40 % or sometimes actually more. For last months this includes weekly canister maintenance to remove blockage in the pre-filter sponge and such, etc. Nothing that would affect the bio filter. I feed once/ day, and don't over feed. Tank is well maintained, generally healthy, but it has been up and running for a long time. And there may have been some fish introduce "un-quarantined' back in the day (nobody goes into any tank now w/o lengthy quarantine.

It just happens that the Cory in question posed for me just a bit easier. Attached are a side view, and then a ventral view, something I have rarely been afforded. The side view shows what I have seen for a long time now, what appears to be a growth. When I see the ventral view, I wonder if it confirms my suspicion that this is a growth of some kind. It almost looks as it began internally and then "split" the "skin" of the corry. Looks awful, although this fish seems to be behaving "normally". I wonder if this is worth starting a new thread with these photos?

 

[Plinkploop]

I hope it's not, but it sounds like neon tetra disease... I have a couple of cardinals left in a hospital tank because of exposure to it. I'd look it up. There's no treatment but they can live for a while with it.

 

[ichthyogeek]

Well if the fish are behaving normally, I think that's a really good sign. You could attempt to surgically remove the mass, but I think that's not going to be an ideal thing to do with such a small fish, since you'd have to surgically remove all the cells, and a procedure on such a small fish would be incredibly traumatic. You could maybe trim the growths and cauterize as necessary as the fish get impaired from tumor growth. Chemotherapy sounds like a really, really bad idea.

With viruses, I just assume that everything's contaminated forever unless it can be bleached. Like, all the fish are probably infected at this point, but by maintaining a good feeding/water change schedule, you're allowing the fish to keep suppressing the virus. There isn't really anything you can do about it aside from palliative care.

 

[DanG]

I am updating this in case others read it. Based on photos of the cardinal, I think I have an accurate diagnosis. Dermocystidium. This may be what is the source of the tumor like growth on the cory as well (though not sure). Isolation is the only thing to do, as it is not treatable, and can release hundreds of spores into the water column.