How do I make a diseased tank habitable again?

[memorywrangler]

In short: My 22 gallon planted tank seems to have some sort of disease established in it.  Most of the fish are dead or probably dying.  What do I do with/to the tank to make in habitable again?

Longer version: I've had two deaths over the last few weeks.  Both were guppies -- one had always been a little on the sickly side and had visible pineconing before it died and other had suffered an injury a month or two prior and had seemingly recover.  I don't know if she was pineconing or not, since her body was bit beat up when I found it.  I chalked these up to bad luck and complications from the injury.

But now both of the female bettas in the tank are listless and pineconing, so I suspect they have all been sick with the same thing.  I'm transferring the bettas to a hospital tank and I'll try to treat them, but I'm not optimistic.

My main question now is: What do I do with the tank?  it's well-established with lots of plants that I like and that are, frankly, going to be expensive to replace.   So what do I do (short of stripping it and starting over) to the tank to make it safe to re-stock?

If it helps, the only other fish in the tank at the moment is a small pleco that I could relocate while treating the tank.

Thanks

[Colu]

On 1/15/2024 at 7:12 AM, memorywrangler said:

In short: My 22 gallon planted tank seems to have some sort of disease established in it.  Most of the fish are dead or probably dying.  What do I do with/to the tank to make in habitable again?

Longer version: I've had two deaths over the last few weeks.  Both were guppies -- one had always been a little on the sickly side and had visible pineconing before it died and other had suffered an injury a month or two prior and had seemingly recover.  I don't know if she was pineconing or not, since her body was bit beat up when I found it.  I chalked these up to bad luck and complications from the injury.

But now both of the female bettas in the tank are listless and pineconing, so I suspect they have all been sick with the same thing.  I'm transferring the bettas to a hospital tank and I'll try to treat them, but I'm not optimistic.

My main question now is: What do I do with the tank?  it's well-established with lots of plants that I like and that are, frankly, going to be expensive to replace.   So what do I do (short of stripping it and starting over) to the tank to make it safe to re-stock?

If it helps, the only other fish in the tank at the moment is a small pleco that I could relocate while treating the tank.

Thanks

What are your water parameters ammonia nitrite nitrate pH KH GH temperature what filtration are you using  what substrate is in the tank do you add water dechlorinator when doing @memorywrangler water changes 

[memorywrangler]

This is after a large water change I did last night, so the nitrites are lower than usual:

• nitrite = 0
• nitrate = 0
• ammonia = 0
• kh=7
• gh=10
• pH=7.2
• 78F
• two sponge filters

I use Prime on all water changes.  The substrate is black diamond sand.

[Colu]

On 1/16/2024 at 1:00 AM, memorywrangler said:

This is after a large water change I did last night, so the nitrites are lower than usual:

• nitrite = 0
• nitrate = 0
• ammonia = 0
• kh=7
• gh=10
• pH=7.2
• 78F
• two sponge filters

I use Prime on all water changes.  The substrate is black diamond sand.

The reason I asked these questions is because multiple fish suffering from pineconing can have an environmental cause your water parameters are fine filtration fine substrate shouldn't cause any issues parasitic infections can cause pineconing in multiple fish when they have a heavy parasite burden if you haven't added anything in last couple of months that could have bought in parasites could be another factor such as stress did you notice any aggression from your female Bettas 

[memorywrangler]

There have only been a few changes in the last few months:

1. I moved in the bettas, but they had been happy elsewhere for many months and the tanks they came from are fine.
2. I started feeding from a new daphnia/moina culture that I got a club auction.  I think the mother culture was outside.

#2 seems maybe worrisome?  but I've been feeding it to all my tanks, and I haven't had problems anywhere else.

 

[Colu]

On 1/16/2024 at 6:38 PM, memorywrangler said:

There have only been a few changes in the last few months:

1. I moved in the bettas, but they had been happy elsewhere for many months and the tanks they came from are fine.
2. I started feeding from a new daphnia/moina culture that I got a club auction.  I think the mother culture was outside.

#2 seems maybe worrisome?  but I've been feeding it to all my tanks, and I haven't had problems anywhere else.

 

Nothing standing out what medication have treated the fish with to answer your original question as we don't no the cause what I would do is leave the tank with no fish for a minimum of 1 month and ghost feed the tank to keep your benefial bacteria going as most pathogens and parasites can't survive longer than 4 weeks without a host some parasites can remain dormant for long periods of time in the substrate I think that unlikely in your case 

[Odd Duck]

On 1/16/2024 at 12:38 PM, memorywrangler said:

There have only been a few changes in the last few months:

1. I moved in the bettas, but they had been happy elsewhere for many months and the tanks they came from are fine.
2. I started feeding from a new daphnia/moina culture that I got a club auction.  I think the mother culture was outside.

#2 seems maybe worrisome?  but I've been feeding it to all my tanks, and I haven't had problems anywhere else.

 

Moving bettas can start interfish aggression even if they’ve been fine previously.  For instance, it’s very rare that people can remove one female from a sorority for treatment, then be able to put her back in the sorority successfully, even if they were clutch mates and together for months and months before the separation.  I read about that type of problem regularly on betta pages / forums.  That may, or may not, have been the issue with your bettas.  The others, hard to tell since they both had previous issues.  If your girls survive, I would keep them together even if one seems ready to go back in the tank before the other.  You may still get aggression with a move, but if both survive, you might get lucky and achieve a reset going back in the tank.  It’s pretty much impossible to predict which you might get - reset or fighting, because, . . . bettas.

As far as “cleaning” disease out of the tank, you could try adding a big dose of peroxide, but I wouldn’t add more than 3 mls per gallon.  Turn off all filters / pumps until you have still water.  Measure your peroxide carefully and pour it over plants and substrate (it will sink to the substrate), try to avoid any remaining live animals, and leave it for 10 minutes.  Pull out any hardscape you can and treat separately.  You could also pull out all live animals, drain the tank as low as possible, and spray peroxide over everything until saturated, and leave it for 10 minutes, then rinse with dechlor water, drain again, and refill the tank.  Draining makes the peroxide more concentrated on whatever it touches compared to mixing it in the water.  Spraying on everything WOULD kill any snails, shrimp, etc, that were left in the tank compared to the carefully measured amount of peroxide put into water.

There’s no guarantee it will work to eliminate disease, but it’s about the only thing you can do that would be plant safe.  Short of reverse respiration on the entire tank.  Obviously all fish, snails, and shrimp would need to be removed for reverse respiration treatment and you could run the risk of a significant hit to your biofiltration with reverse respiration since it would knock out a lot of the bacteria that coats the substrate, plants, hardscape, glass, etc.

Honestly, I would treat the girls with Maracyn-2 in food if possible, and keep them separate for at least 1 month even if they look fantastic in a couple days or a week, keep watching.  Don’t put them back in until they’ve been fully healthy for a full month.  I would just monitor the tank and let it ride for at least a full month.  Blind feed if you need to maintain the BB’s.  If you can’t monitor the pleco well in the tank, move it to a tank where you can monitor better.

[Kat_Rigel]

In my opinion, you don't have to do anything.

Diseases must have a host to survive. In this case, the host is your fish. If this was my tank (especially aquascaped/nice rooted plants,) I would leave the tank alone without fish for 2 weeks, preferably 3 to be safe. Do not feed during this time (no need, because there's no fish. It would only increase nitrates.) Feel free to add ferts as usual. Maybe do like one or two water changes. That is exactly what I would do.

In my opinion, all tanks have some tiny level of ich, some tiny level of bacteria, some tiny level of etc etc. Fish get sick when they are weak for some reason, with the most common reason being moving (shipping, coming home from fish store, etc.) or poor water quality. When one fish gets sick, now you have an infected individual that is making lots and lots of germs/bacteria/pathogens which means its more likely your other fish can catch it, especially if water quality is the culprit since they are all experiencing that stress. I suspect that moving the bettas to a new tank may have been the catalyst, which is just bad luck. Sometimes you don't do anything wrong and things just go wonky. I don't see that you did anything obviously wrong.

 

Tl;dr Leave it for 2-3 weeks and it should be fine for new fish.