Mystery Fish Deaths

I have had my 55 gallon for almost a year. I still consider myself a beginner. I have had two mystery deaths in the past week.

First my pearl gourami suddenly had a tail that had been chewed on, grew a curved spine, disappeared for 20 hours, then found half eaten.

I did a 45% water change and my nitrates were 80 ppm probably due to the dead fish being in there so long. Otherwise my tank is usually 0/0/20.

Two days later I notice my BN pleco eating a fish. What the heck?! I finally figure out my black guppy is missing. I specifically saw him just a few hours earlier. I had admired how great he looked! I checked my parameters and they were down to 0/0/20. What happened? My guppy looked great. Could my BN pleco have attacked? He is still very small. I had that guppy for almost a year. Now I am terrified my other fish will die. My BN pleco has been in the tank for a little over a month.

 

what fish do you have in the tank right now?

 

I doubt the pleco killed your guppy. Most likely, if you didn't quarantine your fish when you added it to your display tank a month ago, you introduced a parasite or bacteria that has slowly weakened your fish.

 

what fish do you have in the tank right now?

Right now, after the two deaths, I have:

10 harlequin rasbora
7 albino corys
2 male guppy
2 male platy
1 male molly
1 tiny BN pleco
1 ghost shrimp

I doubt the pleco killed your guppy. Most likely, if you didn't quarantine your fish when you added it to your display tank a month ago, you introduced a parasite or bacteria that has slowly weakened your fish.

No, I didn't quarantine. My husband refuses to let me have another tank set up for quarantine. I only get my fish from my LFS which has been good so far...until now I guess.

 

I don't see any fish killers in there, it might be something else.

 

Right now, after the two deaths, I have:

10 harlequin rasbora
7 albino corys
2 male guppy
2 male platy
1 male molly
1 tiny BN pleco
1 ghost shrimp



No, I didn't quarantine. My husband refuses to let me have another tank set up for quarantine. I only get my fish from my LFS which has been good so far...until now I guess.

If you have noticed any of these symptoms it would be easier to diagnose underlying issue with fish. The finrot is most likely a symptom of an underlying issue.

Have you noticed any fish rubbing on objects or gasping for air?
Have they all been eating?
Any appear healthy but have been spending time alone near heaters or air stone?
Any fish turning there backs to front of tank for long periods of time?
Noticed any white feces?

 

No matter how good a LFS is, even if they practice qt processes themselves likely wouldn't make much of a profit off of fish at market price and likely would go out of business if they could guarantee 100% safe fish...would take a vet or scientist swabbing each fish and running tests with thousands of dollars in equipment. I know many hobbyists including myself that qt fish for 4 to 6 weeks even if they get them from the most renowned breeder on the planet. There is the option of proactively treating the whole tank every time you add a new fish if you absolutely can't set up a qt. There aren't many safe and inexpensive options for this, but Paraguard for ich, then apI general cure in medicated food (for prazI and metro.) May help you at least cover a few of the more common issues. One deals with tapeworm, the other with many internal and external parasites. You could do general cure in the entire water table, but that's pretty expensive. Each treatment should be administered seperately. That's not a fix for everything or what is always considered the best practice by any means and researching others experiences with the meds with certain fish is wise. You are going to want to steer very clear of antibiotics if at all possible. They can wreak havoc on your biofilter. Erythromycin may be the safest. Otherwise, without qt, its just a risk we have to take. Perfectly healthy looking fish can carry stuff that can't be seen or even show any external symptoms for a long time. It may even be that a new fish you added caught something it is more sensitive to than the other fish from one of your current fish. Another note on a quarantine. It doesn't need to remain set up all the time. Just make sure you are doing large water changes daily or have some cycled media on standby. Maybe if you discuss that with your husband you could keep an empty 10 gallon tank in the closet or basement, garage, whatever and only break it out when you are buying a new fish. Once again, this isn't the gospel or even necessarily a reccomendation, just a few ideas that may help in the future. I also highly doubt the pleco attacked the fish, was likely just trying to do its job and clean the mess up. The bad thing about that is, if the dead fish had a disease, the pleco probably has it now as well.