What Should I Do With Tank After A Death?

A few days ago, I bought a betta from Petco and placed him in my cycled 5-gallon planted tank. I did not bother quarantining him, since he was completely alone in the tank. I chose the healthiest looking one, and he seemed fine when I first got him in the tank. He was swimming around and exploring, and would even flare at me when I got up close to the tank. He built a huge bubble nest in his second day in the tank. I was thinking everything was going well.

The only issue I could see was that he was not eating, and I thought maybe he was too busy defending his bubble nest to notice the food pellets sinking right past him. I figured he would figure out the food eventually.

Yesterday, I found him dead, along with white stringy stuff lying on the gravel. I tested my water, and my parameters were fine, except being a bit high in ph. From everything I've read, they should be able to tolerate a range of ph and altering it could do more harm than good. I did read that white stringies are indicative of parasitic worms.

I would like to try a betta from a breeder in hopes that it will be healthier than the Petco one. My concern is the possibly contaminated tank. Should I discard everything in it and start brand new? Or perhaps medicate it? Or just wait and let the parasites starve off? Do the eggs have a long dormancy period?

 

This thread covers it really well: Cleaning/sterilizing a tank after a fish dies, what needs to be replaced?

 

Thank you very much for the link! Good info, but definitely not what I hoped to hear.

Definitely not looking forward to tossing out my filter media and starting over. This also sounds like I will need to get rid of my plants, since they can't really be sterilized, nor can my Eco Complete substrate. I'm starting to see how this is can be an expensive hobby, even if you find all the equipment on the cheap.

 

The most important thing is to find out why your fish died so it doesn't happen again.

Most fish pathogens are ubiquitous. They exist in all aquarium water. Even if you were able to sterilize your tank, you wouldn't be able to prevent reintroduction on new plants, fish, etc.

 

I bought two guppies that died within 2-3 days of purchase in my QT tank. They had white stringy poo indicative of internal parasites. I rinsed out the tank and sand well and left it empty for a week. I did not toss the filter media either. No issues.

 

Internal parasites don't kill that quickly, if at all. A good parasite doesn't kill its host because that often means its own death. White, stringy feces could just be shed intestinal lining from not eating. I had a severum that showed no signs of parasites at all. When he was several years old, I dosed the tank with praziquantel and tapeworms came streaming out of him.

 

AvalancheDave I don't know if you're taking to me, but my guppies never ate either the few days I had them. They also ballooned up like dropsy-level but without the pineconing. They died within a few hours of ballooning. I really don't think there was anything I could've done for them. I figured, after seeing the poo, that it was parasites. I haven't seen anything before or since that happened. But I've had no issues with the tank and I didn't do any special sterilizing or anything.

 

The most important thing is to find out why your fish died so it doesn't happen again.

Most fish pathogens are ubiquitous. They exist in all aquarium water. Even if you were able to sterilize your tank, you wouldn't be able to prevent reintroduction on new plants, fish, etc.

I honestly have no idea why he died. Everything seemed to be going really well. The tank was previously occupied by my other betta, who was doing well in it, and is still doing well in his new tank. I'm not really sure how to go about finding out why he died. I would hate to have the same thing happen again.

Internal parasites don't kill that quickly, if at all. A good parasite doesn't kill its host because that often means its own death. White, stringy feces could just be shed intestinal lining from not eating. I had a severum that showed no signs of parasites at all. When he was several years old, I dosed the tank with praziquantel and tapeworms came streaming out of him.

Oh my goodness, that sounds horrific! I hope that's not how he went.

 

Oh my goodness, that sounds horrific! I hope that's not how he went.

He wasn't harmed by the worms coming out of him. He just showed no symptoms at all for years despite having a bunch of them.

 

I've treated empty tanks in the past after fish died. It seemed to work as the fungus growing within the tank, which was the cause of the fish's death, disappeared and the newest inhabitants have been unaffected. You'd really need to know what was the cause to be certain you treated for the right thing, and you'd have to continue feeding the tank to keep your cycle going aswell.

 

He wasn't harmed by the worms coming out of him. He just showed no symptoms at all for years despite having a bunch of them.

Oh, I meant intestinal shedding. That's what sounded so terrible to me. But yeah, worms flying out also sounds unpleasant.

 

I've treated empty tanks in the past after fish died. It seemed to work as the fungus growing within the tank, which was the cause of the fish's death, disappeared and the newest inhabitants have been unaffected. You'd really need to know what was the cause to be certain you treated for the right thing, and you'd have to continue feeding the tank to keep your cycle going aswell.

Fungus is usually Saprolegnia or Columnaris. Neither is actually a true fungus but they both exist in all freshwater aquariums. Saprolegnia usually only grows on non-living food sources such as uneaten food but can occasionally grow on living fish. Both would have be observed on a living fish to be considered the cause of death. Saprolegnia seen on a dead fish doesn't tell you anything as it's normal. Both are brought on by stress not by their introduction to a Saprolegnia- or Columnaris-free tank. If your new fish haven't been affected it's because they haven't been exposed to stressors not that your tank doesn't have Saprolegnia or Columnaris like every other freshwater aquarium.

Oh, I meant intestinal shedding. That's what sounded so terrible to me. But yeah, worms flying out also sounds unpleasant.

It's not uncommon for animals to shed intestinal lining, especially if they haven't been eating. It looks and sounds a lot worse than it is.

 

Fungus is usually Saprolegnia or Columnaris. Neither is actually a true fungus but they both exist in all freshwater aquariums. Saprolegnia usually only grows on non-living food sources such as uneaten food but can occasionally grow on living fish. Both would have be observed on a living fish to be considered the cause of death. Saprolegnia seen on a dead fish doesn't tell you anything as it's normal. Both are brought on by stress not by their introduction to a Saprolegnia- or Columnaris-free tank. If your new fish haven't been affected it's because they haven't been exposed to stressors not that your tank doesn't have Saprolegnia or Columnaris like every other freshwater aquarium.



It's not uncommon for animals to shed intestinal lining, especially if they haven't been eating. It looks and sounds a lot worse than it is.

Yes it was observed on a then living fish. just a possible solution for the OP if they don't want to restart their cycle. Be wary tho, as some meds will do that anyways