Advice needed. Disease or Evil Fish. 3 dead, 1 certainly dead by tomorrow.

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I love that little device:

hygger Super Mini Aquarium Single Sponge Filter

Installed just to slightly exceed the water surface.

They polish your water by trapping the lightest particles that floats near the top and also creates a flow of bubbles that breaks the surface and prevent any film from appearing.

With a strong air pump they act as real powerheads. If you are not found on air stones that draw bubbles from the bottom to the top. They are a really good compromise between an air stone and a turbine powerhead.

Ok, so with this post maybe I should leave it a week and see how it goes before saying my goodbyes. Whilst also adding in a wafer each morning to ensure its not hunger.

Try to target feed your bottom dwellers in a manner that they interact the least for the moment. And keep observation high.
I thought Red did well on the votes... I wasn't implying she wasn't beautiful
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On my tanks I've used these for internal filter outlets. Allows me to direct water flow to the surface. It's just hoping it fits which is the problem. A 3D print is probably a cheaper option as well if you have access to that.
I thought Red did well on the votes... I wasn't implying she wasn't beautiful
I meant I would pull her out of punishment for being a brute. No beauty pageant for her. I know she is beautiful :)
I meant I would pull her out of punishment for being a brute. No beauty pageant for her. I know she is beautiful :)
🧐 eye of the beholder and all that...
So some of you may seen a post around a guppy I had that I had to euthanise. It was sat at the bottom of the tank for a considerable period of time, not moving, not eating even when the food was near and eventually was going to die and get eaten. If so you will also know that I lost a guppy a day or 2 before. Missing in action (Presumed and after this amount of time surely also dead)

So that was over a week ago. I was planning to replace the Guppies this weekend as that would then be a 2 week period (I don't know what the period should be)

Today I come home and OH NO! A guppy is lying on its back at the bottom of the tank being nibbled by a Cory. (So that is now 3 guppies in the space of a week)
My heart sank as with no more fish loss and no real signs of visable issues with the fish (I inspect often) I assumed I was ok.

I fish the guppy out and go into the routine that its feeding time. Few flakes for Guppies and catfish pellets for the Cory's/Bristle nose.

That is when all hell breaks loose. The Bristlenose attacks everything across the tank, guarding all food across the bottom (35 x 121.5 tank dimensions, so some area to cover)
Now the bristlenose has been known to be a bit of a git at feeding time, but normally its lunge here and there and the other fish skitter off and find food elsewhere or retry. Nothing has been hurt before.

This time it goes all Mike Tyson on one of the Cory's, that shoots off, lands upside down (head down, tail up) in some Java Moss, where it does not move for 5 minutes. At this point I figure farewell my sweet sweet Cory (Note my Cory's are the love of my tank, the rest of the fish are additions) I get my net and lift the lid of the tank.

At this point the Cory moves, slowly and sadly but not dead at least. (So I thought)

It turns around and I see a huge dark red splodge about half the size of its body.

Now I know I will either find the Cory dead tomorrow, or never see it again.

This comes to my questions.

Clearly I am not going to get new Guppies this weekend. Disease is still an option and a new unknown death was discovered.
However given what I have seen, should I be getting rid of my Bristlenose, as beautiful as she is, My entry to last months fish of the month competion. (pssst I know the answer, I need someone else to say it)
Secondly, when should I look at introducing new fish, is 2 weeks too short?
Thirdly, I thought Bristlenose fish were supposed to be peaceful. Could something trigger this, or did I just get a wrong one!

Note, for questions on the disease front.
Water parameters fine and not changed for months.
Nothing new introduced to the tank.
25% Water change each week, conditioned.
Yes, I have a pleco that gets upset when other fish approach him or his hiding place. He has killed several fish, and I have him isolated in his own tank. I could keep him in a tank with an Angel or Discus, and that would be okay. But any other fish, like a cory, or guppy that would venture near his space would be toast. You might consider moving him or dropping off at the LFS. I feel your pain.
So the original injured Cory did not make it, though lasted a couple days longer than expected.

Since then the Bristlenose has murdered another Cory. So today they got taken to my local fishshop to rehome.
They said they won't sell it and one of the staff is going to keep it in their own tank (So I can visit) I think they were just making the parting of ways easier for me :D

All the other fish at the moment seem to be dancing around the tank in celebration, one even has a party hat on. (Could be coincidence)

So I will now play the waiting game and see what develops over the next 2-3 weeks. If all goes well then I can start deciding what to restock with.
One thing I wonder, as a latecomer to the thread - is that little while horse/unicorn an aquarium safe ornament? I haven't seen that one sold for tanks, but then again, I haven't looked for one.
Yes it is aquarium safe(At least claimed) and made for aquariums. From Maidenhead Aquatics, made by AquaOne.

That being said, it means nothing. I bought an aquarium castle also prior to that(Not Aqua One) and the paint started coming off. So threw that away and replaced with the unicorn to keep the little one happy.
So one week on, here we are again.

Whilst the majority of my fish have returned to normality. More dancing, bigger smiles. I noticed one of the Cory's was alot less mobile, largely staying still on an Anubis Leaf or at the bottom of the tank. It was an easy Cory to notice as its smaller than the rest. I think male whilst the other are female.
Today I was sitting watching the tank and out of nowhere the small Cory starts falling from the sky, spiraling round and round and looking pretty horrific with it. It hits the floor and lies on its side. I leave it for 5 mintues and nothing but the movement of it breathing. I put my net in and catch it, it tosses around and comes out again at the top, again spiralling down to the ground.
I will sadly admit, I took no chances given that I have lost so many fish in the last few weeks. It came out and was put to rest.
Could this be parasitic, damaged swim bladder?

Next I started looking more over the other Cory's. It can be difficult to catch all of them at once (Getting easier as the number drop)
Correct me if I am wrong but from the first 3 photo's they look fairly ok.
However in the last photo you will see one of them has a thumbprint sized area or paleness, could this again be hangover from the angry Bristlenose? Something I did not notice a week ago? fish still either injured or stressed that is causing them to fall to parasites etc that they normally would have no issue combating.

All my watertests come back healthy, I used to do 25% water changes per week but upp'd that to 50% the last couple of weeks.

I know my water hardness/PH is more than Cory's prefer. However given they have generally been happy, healthy and playful for around 4 months and it seems odd it would be a problem now at the same time I have had other issues. I feel like that should be ruled out.

I just feel so hopeless again now that I have to reset the clock on getting new fish. (I may not have any soon!)


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I have the same thing with a mature Cory… been going on for about a year… I asked the same question… mine is still alive, and normal most of the time
Over a month ago, I had a Cory that had a grey patch on its side. He was acting abnormally and flashing. I treated him with a dose of SeaChem KanaPlex, and he healed up. He is doing fine.


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