Fish keep dying and not sure what to do...

[jfeldie]

I'm a novice with a 100 gallon salt water tank. I actually use a local guy(self taught hobbyist) to take care of my tank. But with all the lost fish, I wonder if something is being missed and I don't know enough to figure it out on my own or where I should even start. I've lost 4 fish since August and I'm in the process of losing a fourth. Except for one, they all exhibited the same behavior...stopped swimming, just hang out in one place in the tank and sometimes come out to eat. They usually last a few days in this state before passing away...I had a Desjardin's Sailfin who died suddenly. My husband thinks he ran into a rock and knocked himself out but he never revived (added to tank 6/10/21, died 8/18/22). My Blue Hippo Tang was the next to go (added to tank 8/22/20, died 9/12/22). My Yellow Tang died a month later (added to tank 9/22/20, died 10/23/22). A Blue Damsel fish also died (added to tank 7/26/20, died 11/17/22). And now my Neon Puffer is showing the same signs and I'm guessing I will be losing him in a few days (added to the tank 6/8/22). Other than the change in behavior, they look healthy...nothing on their bodies to indicate a disease. Any suggestions would be greatly appreciated. The guy who helps with the tank isn't sure what's going either. Thank you for any help/suggestions...

 

[griss]

What do water tests show?

Ammonia
Nitrate
Nitrite
pH
Alkalinity
etc

 

[jfeldie]

So, I grabbed a test kit and checked my water. As I mentioned in my original post, I know nothing. I have someone who takes care of my tank but there doesn't seem to be a good explanation as to what is happening in my tank.
My test results have no baseline and my Nitrates were at the highest level so I'm going to test them again.
Ammonia - 0 ppm
Nitrate - 160 ppm
Nitrite - 0 ppm
pH - 8.0
Alkalinity - my test kit didn't have a tester for this one.
It's a 100 gallon tank that has been running since July 2020. I had one issue with the tank back in April 2021 and we quickly resolved the problem and fixed it. Otherwise it's been fine. I currently have 4 blue damsels, 2 clown fish, 1 coral beauty, 1 small sailfin, 1 wrasse, 1 neon puffer, 1 fox face, 2 chocolate chip starfish and 1 hermit crab.
I know the Nitrate is super high but would that kill the fish over months? I'm going to start testing and keep a record for myself. I've planned on learning more but just haven't had the time which is why I have someone with experience help.

 

[griss]

@Dr. Reef Any thoughts here?

 

[kfisc]

Some wide-ranging guesses: Something has changed in your water supply? As in your municipality has heavily dosed/suffered a spill with something toxic and the RODI isn't catching it? Your RODI needs new cartridges? Maybe a Poly Filter to catch a prior unknown toxin?

Also, you've lost four fish, but have 13 left: I'm going to say there may not be enough confirmation for a pattern as much as the unfortunate random losses that can occur. Good luck!

 

[Dr. Reef]

are fish flashing twiching scraping against rocks sand or objects etc?
Are they hanging out on top of the tank gasping for air?
Can you list all the livestock you have in the tank?

 

[jfeldie]

No twitching, scraping or hanging out at the top. The ones that have passed usually hid and stopped swimming or weren't acting "normal". For instance the neon puffer spends most of the day sitting on the bottom of the tank and isn't sleeping in his normal spot at night. Sometimes he'll swim a little bit and he does eat.
Here's what is in my tank: 4 blue damsels, 2 chocolate chip starfish, 1 sailfin (small), 1 foxface, 1 coral beauty, 2 clown fish, 1 red line wrasse, 1 neon puffer and 1 hermit crab. Everyone besides the puffer seems to be acting "normal".

 

[Dr. Reef]

Have you noticed any stringy poops. Any other unusual behavior. Breathing heavy etc.

 

[jfeldie]

The only fish currently exhibiting unusual behavior is my neon puffer. Everybody else seems normal.

 

[Dr. Reef]

160 ppm nitrates are no high enough to kill fish. although i wuld bring them down under 50ppm. I would keep an eye on them and see if there is aggression maybe or some fish cahsing it etc. any stay voltage or maybe carbon use etc sometimes these things can effect certain fish.

 

[Dr. Reef]

only thing i know can kill tangs that fast and keep spreading from fish to fish is velvet or ich. but in both cases you will see salt like white specks on the fish and on thier fins.. You can try a freshwater bath to to see if behavior changes for few days after the bath. if you can post some pics of the fis or video it may reveil something.

 

[jfeldie]

It's been a busy week but I've tried to watch the fish as much as possible and haven't seen any aggression between the fish. Everyone seems to be doing well. The puffer is still acting strange but he continues to eat and swim. He does seem to spend more time than previously sitting on the bottom of the tank. He does have 2 spots on his back that appeared this weekend. I tried uploading a video but I couldn't get it. I was able to snap a picture but it's not great. Somehow he knows I want a picture and whenever he sees me he decides to go for a swim so it's a little blurry. I did reach out to the guy who helps me with my tank about the freshwater bath.

Just out of curiosity, could there have been a "broken heart" relationship between my tangs? Is that a thing with fish?

Thank you again for all of the feedback.

 

[Rd62rdstr]

Just an observation, it appears you have plastic plants in the aquarium. Are there any other decorations? Sometimes these man made decors are cheaply made and the paints used can affect the fish. Nitrates will kill fish slowly over time, so I wonder how long the nitrates have been that high. You should definitely do some water changes to bring them down.

 

[BeanAnimal]

I would also not fully count out aggression. I lot can go on when the lights go out... A fish that gets poked around all evening for weeks on end can be stressed to the point of sickness or death. We just don't always see the extent of it because it happens quickly and often in the dark.

You have lost a small percentage or fish in a mixed community. Chalk one or two up to bad luck, one or two up to aggression or other issues. I don't see cause for alarm. I would (regardless of who takes care of the tank) invest in a few decent test kits (Salifert, Red Sea, etc.) and not rely on test strips or off brand kits. I am not huge fan of the accuracy and repeatability of the Hanna Checkers, but they are great for spot/sanity checks of general parameters.

 

[leebca]

Just an observation, it appears you have plastic plants in the aquarium. Are there any other decorations? Sometimes these man made decors are cheaply made and the paints used can affect the fish. Nitrates will kill fish slowly over time, so I wonder how long the nitrates have been that high. You should definitely do some water changes to bring them down.

Sometimes the artificial decorations have a lead 'anchor' that sometimes comes in contact with the water.