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Unexplained fish deaths, no symptoms.

15K views 23 replies 5 participants last post by  JDM  
#1 · (Edited)
Tank is 35 gallons, been set up since October.

Recently changed to sand substrate in late December, tank came through fine. The tank is moderately planted with Wisteria, stems, crypts, and some swords as the latest additions. Added new driftwood recently, kept an eye out for any fungus or anything and saw nothing, so I don't think that's the cause. Some plants are wild caught so there is a fear of pathogens, but they were cleaned well before addition to the tank and the latest additions were over a week ago.

Tank inhabitants are/were a Pearl Gourami pair, 8 harlequin rasbora, and 8 kuhli loach (4 adults and 4 juveniles).

On the first I lost one of my loaches. No symptoms, was eating fine and swimming around great the day before. I found him dead the next morning, nothing unusual about the body. Tank water tested normal, I thought it was just a freak incident.
However, ever since then most of my loaches have been hiding, which for them is not normal at all.

On the fourth I switched to a Fluval 206 canister. I went ahead and removed my old HOB filter as I figured since the bacteria is already established on the wood and sand, plus the plants, that I would be okay. Water has tested normal on the API Liquid test kit.

Today one of my female harlequin rasbora started swimming oddly during spawning (more than the regular flipping to lay the eggs under the leaves), and passed soon after. I was very upset and tested the water to check, and had normal readings (Ammonia 0, Nitrite 0, Nitrate 5).

Later on I noticed three more dead rasbora right before bedtime. No prior symptoms and nothing odd on the bodies.

I'm getting incredibly frustrated and upset and worried, as I have no idea what could possibly be happening.




It may also be worth mentioning that about 2 weeks ago I noticed white areas on the pupils of my female Pearl Gourami's eyes, and at first worried about a fungal infection but after some research I'm pretty positive that she scratched them on the dirftwood somehow, as the male will sometimes chase her towards the driftwood. It's been healing on it's own and she's showed no symptoms of stress or difficulty swimming or lack of appetite.

If anyone has any advice I'd really appreciate it. I'm honestly near tears. I'd really been thinking I was doing a pretty great job at taking care of these fish, and yet now...I have no idea.

There are pictures of the tank in my thread, Adventures of the 35 gallon if anyone would like to check them out. A few plants have been added since then.
 
Discussion starter · #5 ·
This morning all of the rasbora are dead except for one.

I'm always as careful as I can be about rinsing my hands before placing them in the tank but I suppose it's a possibility that something was introduced...but my Pearls have shown no adverse affects. Then again that doesn't say much considering I just lost 7 rasbora in the space of a day.

I haven't tested GH, KH, or PH in awhile, I'll do all three today before a massive water change.

The wood leached some tannins as was normal, but only enough to lightly stain the water. I truthfully have no idea if it's the wood or not, but it's been in there for, say, 2 or 3 weeks? Driftwood is from the LFS, it's mopani. I've had two other pieces from there before, both mopani, and they were in there for months.

I suppose there could have been a spike, but I'd been watching my params to be sure. It is possible. I just...I can't think that with all the plants that a spike would get so large as to kill them.

No, no one with access except for me and my parents. We do have kids over occasionally but I always make sure they don't venture near the tank, as it's in the back of the house.

Mine have never been so hidden before, and always came out to eat and investigate the tank. Now I'm lucky if I can even see two of them. I haven't seen a baby in awhile so truthfully I don't even know if they're alive either.

I feel like a failure.
 
Discussion starter · #6 ·
Oh, and the filter was second hand but still in all the packaging. All the media was still in plastic wrap, nothing had been used before.

The guy said it wouldn't work on his tank because of his stand, so he never used it.

I can't think that it's anything in the tap either, as all the fish in my mother's tank are doing fine.
 
Discussion starter · #10 ·
Ammonia - 0
Nitrite - 0
Nitrate - 5

I forgot to mention, we had the house and yard sprayed for pests as per normal on Monday. My room does not get heavily sprayed, and I always leave a window open to disperse any fumes.

I haven't changed any products except I switched from TetraMin foods to New Life Spectrum pellets on Monday.
 
Discussion starter · #12 ·
All the filter media except the bio material was rinsed. I didn't use carbon in the filter because I had heard that it absorbs plant nutrients, so that basket just has some floss stuff in it.

Pulled the newest wood piece and am doing an 80% water change. I haven't observed any growth on the wood, but it's possible that something was introduced. I'm not ruling anything out.

One of the plants was placed in a day long quarantine in chlorinated water in a cabinet to help kill off the algae growth. The others...no. I rinse, scrub, and prune them before addition to the tank but again, I'm not ruling it out.
 
Discussion starter · #19 ·
Yes, I still have the carbon in the packaging. I set it aside just in case, I'll add that to the tank. Should I rinse it first? It's in a little black bag. I've never used carbon before.

The tank is half covered in glass for the light to sit on, the front is left open because the plastic lid broke. I'll be looking in to a full glass cover after this just to be safe. I love the look of an open tank but I'm incredibly paranoid right now. I feel so guilty and awful.

The last rabsbora seems to be normal, although I believe she is a little stressed being "alone" in the tank.
 
Discussion starter · #23 ·
I just...we've never had this problem before. And the spray is just that jet of liquid onto the edges of the carpet. We've never had this problem before, or even with our outdoor pond that is near the wall outside that gets sprayed. It's not that it isn't a possibility, but...it just seems odd.

I just wish I could narrow it down specifically to one thing. Because now I truthfully have no idea if my tank is even safe, or ever will be.