Chromis Veridis - 3 Months in Tank, Unknown Illness or Injury

[mechaman241]

Background: I have had three Chromis Veridis for about 3 months now in a 5 month old 29 Gallon tank that is very stable, although a bit on the dirty side nutrient-wise. The other two are showing no signs of stress or illness. No other tank members are showing any signs of stress or illness. All tank members have gotten along very well, no signs of aggression outside of normal Chromis pecking order behavior. Corals are all healthy and showing moderate growth.

I don't have a build thread yet for any of my tanks, mostly a lurker, so here's the details for this tank.

29 Gallon STD tank
5 months old
10 lbs live-rock that came from LFS
1.5 inch avg sand bed depth
Ammonia: 0
Nitrite: 0
Nitrate: 25-30
Phosphate: 0.8-1
Alkalinity: 9-10
Ph: 8.0-8.3
Temp: 79F
Salinity: 1.025-1.026 (ATO with RODI)
Calcium: 360-390
Water appearance: very clear with extremely light floating particulates
Water Changes: 5 gal every other week, reef crystals modified for alkalinity match
Tankmates: 1x Cleaner Shrimp, 2x Emerald Crabs, 5x Mexican Turbos, 5x Nassarius, 1x Trocus, 2x large bristle worms (hitchhiked), some aptasia (not under treatment yet), some vermetid snails (not fighting them yet either), 1x small Zoa Colony, 1x small Hammer, 4x small NPS gorgonians, 2x small GSP, 1x small pulsing Xenia, plenty of pods, plenty of diatoms, plenty of algae
Feed: 3x a day-hatchery diet slow sink pellets (20 or so tiny pellets), 1x a day-1/2 tsp reefroids, 1x a week 1/4 tablet frozen mysis or marine feast
Supplements: Reef complete, Iodide, reef plus, seed
Equipment: hob, UV, skimmer, heater, smatfarm 90w, 1x 500gph power head creating a top to bottom gyre across the tank

Three days ago this Chromis initially was hiding in it's sleeping spot even after the lights came up and would not come out for the first or second feeding. When it finally came out, the whole head looked like it would not un-camouflage. It fed very lightly during the third feeding, maybe two pellets, but was swimming normally. Yesterday it came out normally but was not swimming with the other two, who kept circling back to try to bring it with them to their swimming spot in the flow. It did not eat well yesterday either, but some of the blackness on the head started to fade. Today, I fed mysis and it ate lightly again. I noticed it breathing heavy despite more dark coloration fading, but it is also now having a problem staying afloat. If it doesn't aim up, it starts to sink and has rested on the power head suction mount several times.

I am pretty sure it's not being bullied, as the other two keep trying to go over to it and get it to go to their normal swimming spot with them. The dark markings are the same on both sides, so I thought maybe injury to the color nerve, but I can't imagine from what and breathing is now labored, not improving. There are no visible sores or pests on close inspection that would lead me to believe uronema or flukes. Most of what I've been reading today has either not aligned to what I'm seeing or doesn't have any resolution other than a reported death. Does anyone have any ideas or solutions that have worked with the described symptoms?

The best pics I could get,

 

[vetteguy53081]

Background: I have had three Chromis Veridis for about 3 months now in a 5 month old 29 Gallon tank that is very stable, although a bit on the dirty side nutrient-wise. The other two are showing no signs of stress or illness. No other tank members are showing any signs of stress or illness. All tank members have gotten along very well, no signs of aggression outside of normal Chromis pecking order behavior. Corals are all healthy and showing moderate growth.

I don't have a build thread yet for any of my tanks, mostly a lurker, so here's the details for this tank.

29 Gallon STD tank
5 months old
10 lbs live-rock that came from LFS
1.5 inch avg sand bed depth
Ammonia: 0
Nitrite: 0
Nitrate: 25-30
Phosphate: 0.8-1
Alkalinity: 9-10
Ph: 8.0-8.3
Temp: 79F
Salinity: 1.025-1.026 (ATO with RODI)
Calcium: 360-390
Water appearance: very clear with extremely light floating particulates
Water Changes: 5 gal every other week, reef crystals modified for alkalinity match
Tankmates: 1x Cleaner Shrimp, 2x Emerald Crabs, 5x Mexican Turbos, 5x Nassarius, 1x Trocus, 2x large bristle worms (hitchhiked), some aptasia (not under treatment yet), some vermetid snails (not fighting them yet either), 1x small Zoa Colony, 1x small Hammer, 4x small NPS gorgonians, 2x small GSP, 1x small pulsing Xenia, plenty of pods, plenty of diatoms, plenty of algae
Feed: 3x a day-hatchery diet slow sink pellets (20 or so tiny pellets), 1x a day-1/2 tsp reefroids, 1x a week 1/4 tablet frozen mysis or marine feast
Supplements: Reef complete, Iodide, reef plus, seed
Equipment: hob, UV, skimmer, heater, smatfarm 90w, 1x 500gph power head creating a top to bottom gyre across the tank

Three days ago this Chromis initially was hiding in it's sleeping spot even after the lights came up and would not come out for the first or second feeding. When it finally came out, the whole head looked like it would not un-camouflage. It fed very lightly during the third feeding, maybe two pellets, but was swimming normally. Yesterday it came out normally but was not swimming with the other two, who kept circling back to try to bring it with them to their swimming spot in the flow. It did not eat well yesterday either, but some of the blackness on the head started to fade. Today, I fed mysis and it ate lightly again. I noticed it breathing heavy despite more dark coloration fading, but it is also now having a problem staying afloat. If it doesn't aim up, it starts to sink and has rested on the power head suction mount several times.

I am pretty sure it's not being bullied, as the other two keep trying to go over to it and get it to go to their normal swimming spot with them. The dark markings are the same on both sides, so I thought maybe injury to the color nerve, but I can't imagine from what and breathing is now labored, not improving. There are no visible sores or pests on close inspection that would lead me to believe uronema or flukes. Most of what I've been reading today has either not aligned to what I'm seeing or doesn't have any resolution other than a reported death. Does anyone have any ideas or solutions that have worked with the described symptoms?

The best pics I could get,

This is the beginning of uronema which affects certain fish including chromis. Its best with acquisition to give them a 60 minute bath as a precautionary measure using a formalin based medication including Ruby Rally pro.
This can also be triggered by low salinity levels as well as excess food waste on tank bottom which this protozoan can feed on as often prevention can be more valuable than cure for this.
Fish will have to be quarantined and treated with formalin based treatment which is harder to find, so next option is Ruby rally Pro. Chloroquine Phosphate will also work but must be used precisely. Uronema is not an obligate parasite, and can thrive on bacteria, uneaten food, and waste so besides treatment also maintain a clean tank removing waste daily.
To touch up more on this disease which is an oval ciliated motile protozoan that causes tissue necrosis as seen on fish.
What other fish are in the tank?

 

[mechaman241]

I really appreciate your help! I haven't had any illnesses in my journey as an aquarist that weren't super obvious and matched symptoms by the book until now. Do you think baths and return to the display would be best for the affected fish or should I setup a 5 or 10g hospital tank? I keep a small cycled media bag in my 10g macro-lr-clown tank just in case I'd need it for a hospital tank and have a spare pump and heater I use for mixing that I could repurpose. My LFS is pretty well stocked, but I'll also be passing through the ATL metro tomorrow on a trip so I should be able to find any chems needed. Which would you recommend for a hospital setup and which would you recommend for a bath and return treatment?

Am I wrong in what I've read that uronema isn't likely going to be a concern after 3 months of health and no new introductions? Also, everything I've been reading normally rules out uronema when the coloration symptom is symmetric and sores are not present. It really did look like a pinched forward coloration nerve day 1, not tissue necrosis and onset was sudden, not gradual for the poor dude. It still doesn't look like tissue necrosis, but a melanin issue, the scales themselves are present and not removed or damaged, again why I initially thought injury to the nerve. I would have expected recovery with that over the days though, not a development of rapid breathing and loss of buoyancy with tendency toward sinking on day three. IANA marine biologist though. I do have a 1000x microscope at my disposal and slides/slips if that is able to be used to confirm presence of uronema in some way. I'm not sure how big of a protozoan it is though or it's identifying features.

All water parameters readings listed have been rock stable since the cycle ended, which was to be expected with a live-rock/live sand/Seed start and then pod and CUC intro. There has been an ATO from the start and salinity has never run lower than 1.025 and never above 1.026. Nutrients have been stable and holding at present levels the whole time. Other than the diatom/pod war that's still trying to find it's balance every so often, the CUC keeps the sand bed free of detritus and organic matter, even making dents in the sand diatoms while the pods catch up as that cycle starts to stabilize and balance each round (normal new tank expectations) and a shrimp molting is gone in 24 hours. I was thinking about trying to get down to ULNS levels, but I'm seeing great growth in everything and 25/.8 N/P isn't known to be unhealthy for fish, plus I really like knowing everything is well fed, which is hard with a HOB and ULNS and phosphate is always going to be a little high with reefroids and NPSs present.

I'd love to know more about why you're leaning towards uronema.

My intro-procedure is as follows: temp acclimate, 50% tank water addition to bag, freshwater dip (parasite check), formalin bath, 100% tank water flush, introduce to tank if clean (all were). Corals also went through an appropriate peroxide or iodine complex dip procedure and pest check. The aptasia, vermitids, and bristle worms (non-fire) made it in at the beginning via the live rock... I swear those three will outlive cockroaches...

There are no other fish in the tank right now other than the listed other two Chromis. There were two A. Ocellaris in the tank, but they were removed more than a month ago and there isn't any correlation between that removal and this issue. They are also very healthy and happy in their new habitat. All other tank mates are listed, all inverts, all also healthy and thriving.

This is the Chromis two weeks ago with normal behavior and schooled swimming in the lower current, affected fish to the left, leading the school:

To anyone who reads this: sorry if I'm being super verbose and overly detailed. I've seen a couple threads where there were similar symptoms, but it either wasn't described very well, was a different presentation, or the issue wasn't identified because the fish died prior to identification and treatment. I'm attempting to document as much as possible here in case this is identified and successfully treated for future aquarists to look back on.

Picture of the full tank now with 100% all channels (normally A:5 B:85 C:85 D:85 E:10 F:10, 8 hour run, two hour ramps), no yellow filter. Glass was cleaned two days ago, so a normal 2-day dusting can be seen on the sides especially. The last gravel vac was two weeks ago during water change.

 

[mechaman241]

Day 5 from initial onset of symptoms:

Black discoloration is fading a little bit more, no loss of scales or red lesions. Is staying in the current a bit more today. Breathing has returned to a normal rate. Fed Marine Feast today, didn't eat as well as other 2 Chromis, but did eat decent. Still has pinched belly. Still has a negative buoyancy issue. One thing I noticed is a tendency to hold body curved slightly to the left and the fish is primarily using the pectoral fins for altitude and attitude control.

 

[mechaman241]

Just to close this thread for anyone in the future. The case was a long terminal one. It held on for 2 more months, even looked to be recovering at times, but ended up passing.

I treated it with kanaplex and erythromycin shortly after the last post, to no effect. The curve in it's back never went away completely. The likely ultimate cause of death was stress as it always looked spooked for the last few days, however the cause of the symptoms leading up to it was probably injury.

The fish had paralysis on one side of its body to the rear and could not swim normally and lacked complete control of its swim bladder. It would never recover completely from it's camouflage coloring (the dark marks) and even when having a healthy streak would find the darkest spots in the tank to retreat to. It ate well until the last day and was gaining weight and size when it was suddenly dead on the bottom one morning.

There are three other Chromis in the tank, all unaffected, healthy and doing well, as are all other tank mates (now consisting of one male clown, three green chromis, one flame hawk fish, one scopas tang, one diamond goby, one neon dottyback, and CUC. A post-mortem scrape of the dark areas revealed no outer infections. I'm not skilled enough to perform an accurate dissection of such a small fish, so none was performed. I'm not sure the cause of paralysis would have been revealed via dissection anyway.