What is Killing All of My Fish?!

[kdragon64]

I have recently lost half of my fish for no apparent reason! They look fine one day, and they were dead the next, sometimes two at a time, over the past two weeks. I have had most of these fish for six months or longer. The tank has been up since early February of this year.

I recently added the starfish below, but was told it is a brittle star that eats detritus, so I didn't initially suspect him, but I'm at a loss for the aggressive fish kill I've been experiencing. This starfish is brown and tan, but seems to stay in the same place most of the time, I have not even seen him on the dead fish, although I think he did kill and eat a small emerald crab that was nipping one of his tentacles.

My water parameters are all good and have been steady for many months, 125 gallon tank, temp 78.4, alk 9.5, ph 7.9, salinity 34.5, calcium 540, ammonia 0, nitrite 0, nitrate 10, phosphate 0.15, magnesium 1380, have protein skimmer, filter socks, 4 canisters (with activated carbon, phosgard, nitrate trap and biopellets).

Current tank inhabitants: Bicolor dwarf angel, sailfin blenny, pajama cardinal, stop light cardinal, blue-green chromis, oscellaris clown, firefish goby, blue line cleaner wrasse
I also have the aforementioned starfish, two scarlet cleaner shrimp, three peppermint shrimp, one sexy anemone shrimp, one coral banded shrimp, one mini carpet anemone, 4 emerald crabs, 2 porcelain crabs, 2 feather dusters, one coco worm, one electric eye scallop, pink atlantic urchin, tuxedo urchin, 15 corals, 2 conchs, 2 clams and about 80 snails.

Recent losses: Flame angel, royal gramma basslet, black combtooth blenny, pearlscale butterfly, saddleback butterfly, kauderns cardinalfish, black and white ocellaris clown, engineer goby

 

[Diesel]

When was it you added your last fish?
How did you acclimated the star?

 

[saltyfilmfolks]

You'll want to find the scientific name of the star to know. It's not tough , just takes time.

Also if you're not using some form of qt you'll not know if it was disease from introducing a coral sand or fish recently.

 

[S.O.MLemos]

That’s actually a banded serpent star (ophiuroidea family like the brittle stars)I recently got one too and I doubt it’s him doing the damage. From your list and my experience I’m going to say your banded shrimp is the culprit at night. I had one and he killed royal gramma, yellow clown goby, blue line goby,small clown fish, blue damsel, six line wrasse and scooter blenny (basically any fish that would sleep close to the ground) all within a month finally caught him one morning with the gramma and he couldn’t deny it because his belly was purple. Got rid of him 6 months ago and haven’t lost a fish since. But you lost some larger fish so I could be wrong.

 

[kdragon64]

Last fish was added over two months ago. Latest addition was the star and the second scarlett cleaner shrimp about three weeks ago. Starfish was acclimated with floating drip acclimation over two hours, he seems to be doing fine. My coral banded is quite small, way smaller than most of the fish that recently died, and he's been in there for several months without killing one fish, so I don't think it's him in this case.

 

[Diesel]

Of course on the moment it's a geussing game but how do the dead fish look like?
Any damage?
Pics of the next dead fish would be helpful

 

[kdragon64]

The fish generally looked fine, no fin damage, no visible parasites, only they looked discolored and pale, and some of their remaining color seemed to come off easily on a paper towel after being removed from the tank, which I considered was the beginning of the decay process since I didn't always find them right away. A few that I found later were somewhat eaten by my peppermint shrimp, but I assumed that was after the fact scavenging. Hopefully this is over with and I won't have a need to take pics, but I will post pics if I lose another.

 

[Diesel]

Pay close attention to the behavior of your other fish.
If they have something as in a decease you will see it show up on them or through their behavior.
It's a good thing now to educate your self by reading through all the stickies in the "https://www.reef2reef.com/forums/fish-disease-treatment-and-diagnosis.771/"

 

[kdragon64]

Thanks Diesel. I have had fish die before from ich, which I was able to easily identify, but these fish seem healthy soon before death, no apparent parasites or slime, no erratic swimming, no bouncing off rocks, etc., and so many so quickly has me baffled. A friend suggested I test for O2 levels since I have a covered glad covered tank, but I thought this unlikely since I have a protein skimmer with air tube vented outside to fresh air, open sump in the cabinet, flow near surface of my water, and a cooling fan that blows directly on my sump water if temp goes up by one degree. Shouldn't that be sufficient for O2 exchange?

 

[MichelleRay]

That seems like it would be enough oxygen to me for what it's worth. If you are able you might record the tank at night some time and see if anything weird shows up. Could be something hiding in there that just got big enough or numerous enough to impact fish? My last tank had a rogue bobbit worm show up after a few mysterious vanishings. Thing was a good 2 feet long and I had no idea it was in there for nearly a year.

 

[kdragon64]

Wow, just learned what a bobbit worm is. Those things are crazy. I wouldn't want to have to deal with that. Lucky for me, that's not my culprit. No damage to the fish and they're all just laying on top of the sand.

 

[MichelleRay]

I ended up dismantling. That so and so survived a tap water bath. Tap water! Not even warm tap water! For hours! Anyway those all seem like pretty tough fish as far as they go, which is really weird to me. The starfish looks like a banded star to me too, and anyway if it had decided to go rogue it seems like it would have eaten some of them not just strangled (or whatever) and left them. Some kind of toxin is all I can think of now. Hidden cuke maybe? That got really ticked off by something? It's a big tank so maybe if the fish was close to where the toxin was added, and got a big dose before it dissipated? It's a stretch but I can't really think of anything else. Collective old age maybe but that seems even less likely.

 

[kdragon64]

That sounds like quite an ordeal with such an ornery critter.

Thank you folks for your ideas.

I also thought potential toxin, but have no idea what it could be. I have less than 1 inch of sand, so there are really no anaerobic regions to form H2S.

I guess I'll review more about potential diseases.

Another thing I was thinking is the cleaner shrimp and wrasse are keeping outside parasites to a minimum while allowing gills to get compromised. The cleaner wrasse seems to be actively interacting with the fish almost all the time.

If it is ich, which I know to exist in the tank, is there any safe and effective way to treat in the reef tank? Quarantine of fish has not been effective in the past as I think the stress of catching the fish causes more harm than the treatment does good.

 

[kdragon64]

OK, I just got home and fed the remaining fish and noticed something growing on my pajama cardinal, but only on his head in front of his dorsal fin.
See attached pic.
When I've seen ich in the past, it was all over the body of the fish and not concentrated like it is on this cardinal.
Does anyone have an idea of what this might be?

 

[Rakie]

Need a much clearer picture and a good description.

It could be a bacterial infection, or a bunch of other things. Can't tell from here.

 

[4FordFamily]

The fish generally looked fine, no fin damage, no visible parasites, only they looked discolored and pale, and some of their remaining color seemed to come off easily on a paper towel after being removed from the tank, which I considered was the beginning of the decay process since I didn't always find them right away. A few that I found later were somewhat eaten by my peppermint shrimp, but I assumed that was after the fact scavenging. Hopefully this is over with and I won't have a need to take pics, but I will post pics if I lose another.

This worries me that it could be the strain of velvet that doesn’t often show external spots, rather it affects the gills and kills fast.

Did the fish become cryptic and hide from light before dying? Swim in to powerheads? Breath heavily?

Do you quarantine and treat all fish before adding?

 

[kdragon64]

Thanks for the replies.

The picture is the best I was able to get after taking about half a dozen.
For more info, this growth is white and looks a little fluffy and is actually protruding past the body of the fish on one side.

This Cardinal is swimming around normally, like nothing's wrong with it, ate like normal, stays in the light, is not going to the top nor bouncing off rocks, not swimming in circles... It is not doing anything out of the ordinary behavior wise. The other fish acted in a similar manner, but I did not see this growth on them.

Only one was found stuck on my powerhead, the clownfish, the rest were just laying in the sand.

I no longer quarantine or dip, just acclimate, since I was losing fish right away in the past from that stress. These fish have been with me for months now with no new stressors.

I will look into the velvet idea, do you have any suggested links for the strains you indicated or for any treatments that can be used effectively in a reef tank?

Thanks again.

 

[Diesel]

I wouldn't suggest to do a treatment in your tank rather in a QT or hospital tank.
If many fish already past from this, pretty sure all remaining fish are effected in your tank.
Moving them all out is sometimes not possible with as results a slow dead for the ones that stay behind.
Sorry to bring it that way.
If you had fish passing while in quarantine than you did something wrong to begin with or they were to sick for treatment.
Many hobbyist can say that the right approach lay out by the R2R reefsquad saved many many fish in the past.
In this link https://www.reef2reef.com/forums/fish-disease-treatment-and-diagnosis.771/ you can find many stickies that can assure you a successful QT treatment plan for all fish, that is if you're up to that in the future and even now with the sick effected fish you have on your hand.
Do the right thing and do it for the fish, they didn't want to get sick but had no choice cause the hobbyist knew it always better.
It ain't to late bro.

 

[kdragon64]

I read a lot and followed all the advice when I first switched over to salt water. Dipped everything, quarantined everything, never added live rock that wasn't dried first, etc. Lost a lot of marine life in the process, either from the stress of the procedures or the stress in the quarantine tank.
Despite all that, the main tank still got parasites and the reality is once their in their in. Sure, I could get rid of them by going fishless for a couple months, likely losing more fish from the stress of that process. Then, despite my best efforts to re-establish my tank, have the parasites right back in there again. This surely does not seem like a truly practical solution.
That's why I'm looking for an option that is more practical. I've found some options on other websites for treating parasites that claim to be reef safe and am asking for input on those from folks that have tried them.
If you're not a fan of this method, I understand. But I've tried your suggested approach to avoidance and that wasn't effective. So I'm moving on to try something different.
No-one appreciates losing marine life. Not for the cost nor the loss of life, so we agree on that for sure.

 

[Diesel]

I get your point and you're solid on your approach to cure your fish, all I can say is good luck with that.
Maybe there are some folks here that had success with these methods of a in tank treatment that rid off all parasites in your water and on the fish.