Unexplainable Fish Deaths

TMORGAN1980 · Jan 12, 2023

so it’s been long enough that I think I can post about this. I’ve got a 30 gallon reef tank and about a month and a half ago all the fish started dying off slowly. Some showed weird flesh colored bumps and lethargy and others just disappeared at night after acting completely normal. Of the 9 fish that were in the tank I’m down to two(yellow damsel and fire fish)which have survived and never showed any signs. The last fish died over a month ago. I tried quarantining and medicating but it did nothing to save the fish. I’m considering adding fish back to the tank but what are the odds that I have a parasite the two remaining fish are immune to or just carriers of?

thanks for any input

travis

All water parameters are tested every few days and perfectly fine. Corals are thriving invertebrates are fine

Widdlyscudds · Jan 12, 2023

what are the parameters of the tank? need way more info than that. do you have any photos? I probably can't help you but the folks who can are gonna need more information

vetteguy53081 · Jan 12, 2023

TMORGAN1980 said:
so it’s been long enough that I think I can post about this. I’ve got a 30 gallon reef tank and about a month and a half ago all the fish started dying off slowly. Some showed weird flesh colored bumps and lethargy and others just disappeared at night after acting completely normal. Of the 9 fish that were in the tank I’m down to two(yellow damsel and fire fish)which have survived and never showed any signs. The last fish died over a month ago. I tried quarantining and medicating but it did nothing to save the fish. I’m considering adding fish back to the tank but what are the odds that I have a parasite the two remaining fish are immune to or just carriers of?

thanks for any input

travis

All water parameters are tested every few days and perfectly fine. Corals are thriving invertebrates are fine

What is age of tank and how did you cycle tank and how long ?
Did you acclimate fish and how did you acclimate and again for how long?
How are you testing water?

Water is the lifeline for fish and coral and 9 fish in a 30 gallon pose high concern especially if a newer tank.
PICTURES UNDER WHITE LIGHTING WILL HE HELPFUL IN ASSESSING BOTH THE LANDSCAPE AND SEEING REMAINING FISH

Mr. Mojo Rising · Jan 12, 2023

how long were the 9 fish in the tank? That is a very overstocked 30 gallon.....

Nemo&Friends · Jan 12, 2023

Which fish did you have and for how long? Did they die almost all at once or was their death spaced out? More details about symptoms would be also useful.

JZ199 · Jan 12, 2023

Everyone asked great questions already, I'm commenting to follow along if updated information and photos are posted so I can try to help.

TMORGAN1980 · Jan 12, 2023

Tank was set up in mid June. There were nine fish in the tank for probably four months with no issues. Yeah I know that was bit over stocked but I don’t think that would cause a massive die off to this magnitude. I’ll get some pictures tomorrow when the lights are on and I’ll turn on the way up.
Water tested with Hanna meters or salifert, Sometimes both

Fish were always acclimated at least 30 minutes, sometimes up to an hour. None of the fish died as soon as they were introduced. Everybody was happy for months.

parameters
Salinity 1.026
Alk. 11dKh
Calc. 450ppm
Mag 1350
pH. 8.2
Temp 78
20% water change every 2 weeks

TMORGAN1980 · Jan 12, 2023

Fish that died were 2 clown gobies, they both went first. They both had symptoms first, flesh colored bumps and not eating. Lethargy. Tried Quarantined too late. Then 2 clown fish had symptoms. No bumps just lethargy and not eating. Tried to quarantine as well but too late. Then a dotty back went from fine to barely alive overnight. Last 2 to go were a blenny and damsel which showed no symptoms just disappeared one night. Was waiting to see if the last 2 would disappear to fallow the tank but they’ve been fine for months now.

vetteguy53081 · Jan 12, 2023

With the 9 fish, saturated oxygen is reduced and good water quality is of essence as is diet
The bumps suggest bacterial or something similar causing skin imperfections
Other questions were acclimation, test type
What is current ammonia and nitrate and type of test kits
Type of filtration
Pics really would help

TMORGAN1980 · Jan 12, 2023

Few weeks ago. I’ll get higher light pic tomorrow

TMORGAN1980 · Jan 12, 2023

Ammonia and nitrate/nitrite are 0. I use test strips for that

davidcalgary29 · Jan 12, 2023

TMORGAN1980 said:
Fish that died were 2 clown gobies, they both went first. They both had symptoms first, flesh colored bumps and not eating. Lethargy. Tried Quarantined too late. Then 2 clown fish had symptoms. No bumps just lethargy and not eating. Tried to quarantine as well but too late. Then a dotty back went from fine to barely alive overnight. Last 2 to go were a blenny and damsel which showed no symptoms just disappeared one night. Was waiting to see if the last 2 would disappear to fallow the tank but they’ve been fine for months now.

That doesn't mean that you've eliminated a potential pathogen, though; these fish might have just developed some resistance to it. I would suggest that you remove any survivors and put them in a quarantine tank with hypo (it sounds like you could have had flukes) and then let your display be fallow for the appropriate period of time...if you want more than just two fish in there, of course.

TMORGAN1980 · Jan 12, 2023

I’m perfectly fine just having 2 fish in there. But my kids and wife don’t like a mainly coral tank. In order to get the last two fish out I would have to completely dismantle the tank which I’m not willing to do right now. They both hide under the bottom rocks as soon as I stick a net in there. A local reef tank friend of mine suggested getting a few chromis and introducing them with a quarantine tank on standby to see if a pathogen re-emerges.

Lavey29 · Jan 12, 2023

TMORGAN1980 said:
I’m perfectly fine just having 2 fish in there. But my kids and wife don’t like a mainly coral tank. In order to get the last two fish out I would have to completely dismantle the tank which I’m not willing to do right now. They both hide under the bottom rocks as soon as I stick a net in there. A local reef tank friend of mine suggested getting a few chromis and introducing them with a quarantine tank on standby to see if a pathogen re-emerges.

As the other posted stated, it is highly likely a disease attacked your fish which means the display tank will have to fallow for 45 to 76 days depending on the suspected illness and the remaining fish should be QT and medications added. If you don't then there is a Hugh chance of large die off again as you start adding fish. Their immune systems might help for awhile but eventually the disease attacks them if they get stressed.

vetteguy53081 · Jan 12, 2023

TMORGAN1980 said:
Few weeks ago. I’ll get higher light pic tomorrow

Will need as indicated under white lights.
You placed 9 fish in a tank and relied on $7 pack of test strips to sustain them - test strips work for freshwater as well and notorious for false readings. I would not be surprised if ammonia is closer to 2 - desired is < .025
I Urge you to take a water sample to a trusted LFS that does NOT use API kits and see what results they come up with. You will then realize what is going on.
I mentioned Oxygen earlier and If 1.0 is accurate, its already an issue and if you change water every 2 weeks, I hate to see what it was at the time.
THIS IS NOT A BASHING SESSION but again, your water is the lifeline of your livestock and deemed toxic