Sterbai Dying Off In Quarantine

I have a quarantine tank with problems. I've lost 5 of 8 sterbaI cories over 2 weeks, and don't know why. What am I missing, or not considering? "Fishlore, I could use your help. Ed Henry's kicking my @$$ out there". (Remember The Titans film ref).

Tank info:
20 gallon high. Filtration = AC50, plus sponge filter (med air rate only, due to teeny tiny but oh so quiet air pump).

Parameters:
Ammonia: 0
Nitrite: 0
Nitrate: 5 (seems low for bioload, but I've been keeping up on water changes, so even if it's incorrect, the actual number isn't more than 10-20).
pH: not measured yesterday, but my other tanks typically run around 7.4

Stock:
3 sterbaI cory ±1" (down from 8 – this is why I'm writing here)
7 rummy nose tetra, ± nearly mature size
1 swordtail (wild type) 2"
1 gold ram 1.5"

Meds: Prazipro and Kanaplex

Cories are dying one at a time. Zero visible symptoms of disease (them or any other fish). When set up, quarantine tank was jump started using cycled media (sponge filter and bio media).

Things were fine for about 10-14 days. Over the past 2 weeks, I've lost 5 cories, the most recent being yesterday. Only symptoms are fish that appear skinny, and sort of listless. On one occasion, a fish that died was a bit pale the day before. After the 3rd death, I started medicating despite not having a specific problem. Treated with Prazipro, and Kanaplex last friday. I re-dosed Kanaplex on Sunday, but have lost 2 fish since then, so it's clearly not helping so I've bailed on the last dose, which would have been last night.

The swordtail and rummies appear fine. Ish. Rummies not well colored, but all alive and all eating. The ram is pale and appears to be pumping fairly heavily, hanging out in one place near surface but not gasping (wait, is gasping when they pull surface air, like bettas/gouramis, or is pumping gills the same thing as gasping?). But ram is also good size/weight, and is eating, though not voraciously. So no deaths except the cories.

One other detail: Last night I called the lfs where I bought the cories to inquire about the health of the rest of the batch they have (still 80-odd fish), and they are doing great, no signs of problems. So whatever is going on, it's all on me, not the supplier/source.

Where to go from here? Add all to main tank as soon as 7-days of prazI is up (this Friday)? I'm reluctant to keep them in the quar tank, I think the stocking level is just adding to stress (based on color and behavior). I hate relying on 'fingers crossed'.

TIA!!

 

It could possibly just be stress. I would put in some pvc pipes for your fish to hide in to lessen some of it. SterbaI seem to be some of the more sensitive catfish, so they are also very sensitive to water chemistry. You could also put in some black water extract which would soften your Ph making all your fish more comfortable and stain the water providing a sense of security to your fish. You could even use indian almond leaves in your quarantine to give it that effect.

 

What are you feeding your corys? How often do you do water changes?

 

Thanks for the easy-to-implement suggestions DutchAquarium . I love it when actionable items are simple to execute.

mattgirl, they mostly get a once/day mix of bugbites for bottom feeders (which I've seen them park over and nosh happily), and Tropical flakes, finger-ground to fine particles.
Occasionally, also Tropical algae flake (also finger ground), Hikari's FD brine shrimp-spirulina cubes (tiny pieces), and frozen mini-bloodworm.

 

Thanks for the easy-to-implement suggestions DutchAquarium . I love it when actionable items are simple to execute.

mattgirl, they mostly get a once/day mix of bugbites for bottom feeders (which I've seen them park over and nosh happily), and Tropical flakes, finger-ground to fine particles.
Occasionally, also Tropical algae flake (also finger ground), Hikari's FD brine shrimp-spirulina cubes (tiny pieces), and frozen mini-bloodworm.

It sounds like they are well fed. Some folks don't realize that corys are not algae eaters and the poor little guys suffer. I see that isn't the case here. I am sorry for your losses. It is never easy and even more so when you can't get to the bottom of the problem. Hopefully DutchAquarium 's suggestions will help.

 

I'd worm them

 

Thanks DoubleDutch I was hoping you’d chime in
I dosed the tank w prazI this past Friday, would that provide the treatment ur recommending?
Follow-up: if they did have worms, and having dosed prazI on Friday (and assuming I didn’t somehow screw up the treatment), could lingering effects/damage caused by worms still have driven mortalities Sunday and Tuesday? [that came out way more convuluted than I hoped it would - do u follow my question?]

 

Update: 2 more SterbaI dead today. As before, no outward symptoms (that I can see). Only 1 remaining. With nine other fish in the quarantine tank, I can no longer justify any special measures focused on the cory, and am more concerned about the others.

So my most important question at this point is, should I move the remaining fish (7 rummies, 1 ea of gold ram and swordtail) from my quarantine tank into my main tank, given that the only issue I can see in the quarantine tank appears to be stress. Not only do I not see any outward signs of disease, I administered fairly reliable treatments for parasites and gram-negative bacteria (prazipro, and Kanaplex respectively).

I appreciate any input y’all have to offer. Many thanks!

 

I know this seems obvious but have you been putting your hands in the tank without washing them? That’s probably the only thing I could think of other than worms. I’d move the other fish to the DT, how long have they been in the QT for? Also, what was the ph of the store water, if it is too different than your QT water, that might be the problem.

 

I know this seems obvious but have you been putting your hands in the tank without washing them?

I won’t say it’s never happened, but I’m careful about it. And my 2 other tanks are fine, so something about this tank/setup/etc is off. And before u ask, no, my hands do not go from q tank to others without a thorough OR-type scrub.

how long have they been in the QT for?

Purchased and quarantined March 2. They would have been in dt already except a) dying, obviously, and b) I got a fish from wide for b-day on 13th, which reset clock for quar (eg went from q+11d on 13th back to zero). Not sure if I’m rationalizing all this correctly, wouldn’t be the first time I’ve been accused of overthinking something.

Also, what was the ph of the store water, if it is too different than your QT water, that might be the problem.

Not certain, but worth asking. I spoke to lfs last night and mentioned I was keeping the fish in “gta tap” (GTA = Greater Toronto Area), and they said no prob, staff keeps hers in same.

 

Okay, well I’d move the fish over, the cories probably have a lowered immune system so its not long till they get something contagious and apparent.

Next time you go to the store to fet fish I’d actually test the ph of the water that they came in, I’m in the GTA too and I’ve gotten fish from a store really close by with a crazy different ph than me. I just thought that because sterbias are kind of delicate and if the ph was too different it could’ve affected them only because they are less hardy than the other fish(although I’m suprised none of your rummynose’s have died at all that's really good)

 

Next time you go to the store to fet fish I’d actually test the ph of the water that they came in, I’m in the GTA too and I’ve gotten fish from a store really close by with a crazy different ph than me.

Good suggestion, certainly not hard to do. In this case, as described above (and I know I write long, so can't expect everyone to read every word), the cories were in the q tank for about 2 weeks before I saw first mortality, so I'm inclined to think the pH was not hugely different. But I'll check next time.

I’m suprised none of your rummynose’s have died at all that's really good

Agreed. Small blessings, right?

Thanks for your input!

 

So part of what’s been bothering me the most about this entire quarantine tank problem has been not having any viable theories as to what’s going on. I think I may have finally made a breakthrough. One relevant bit of information I had not included above is what I thought was fungus growing all over the aquarium glass. Being a newly set up tank, an explosion of fungus didn’t strike me as being a big deal, in fact rather expected. But then I came across some pictures of huge mats of tiny hydra all across aquarium front/sides that looked just like what I had thought was fungus on my glass.
I have an excellent tiny magnifying lens, and as soon as I got home I practically ran up to the quarantine tank and checked for myself. Clear as day, there they were, hundreds and probly thousands of tiny hydra all over practically every surface of the tank. Hopefully the video link here works, I’ve never uploaded a video this way before, but this is my tank earlier today.

So here’s my theory, and I welcome any feedback. It’s my understanding that hydra can and do sting, capture, and consume fry, tiny shrimp, and all manner of similarly small creatures. How they affect fish appears to be less well-known, or at least pretty murky on the web. Bear in mind my poor cories were barely an inch long, caudal fin not included. Being scaleless, and with sensitive barbels constantly surfing the substrate and glass, I would imagine they took virtually constant stings, and the hydra venom could’ve accumulated in their tissues. I have no trouble imagining, based on the sheer density and number of hydra in my tank, that this venom load could have been fatal.
chromedome52 sorry to drag you into this discussion by name, but in my research I came across an old thread from May 2016 where you wrote about hydra affecting larger fish (Is this the beginning stages of Hydra or no?), so I’m particularly interested in your feedback here.

 

I should also add that most websites discussing hydra note that when their population explodes, it’s a sign of overfeeding, because the hydra are basically consuming and thriving off the micro organisms that thrive from the excess unconsumed food. So part of fixing this problem is cutting way back on the amount of food I’m putting in the tank. I’ve also just started a treatment of No Planaria which is supposed to be quite effective. I’m hopeful that within the three day treatment the hydra will be wiped out and I can put the remaining fish in my display tank.

 

Sorry, but those are not Hydra. The tendrils are too short and bushy, looks more like Bryozoans to me. Harmless to fish, they are filter feeders I think. Your treatment may not affect them, I don't know what the active ingredients are in that product.

 

Does the treatment affect fish? If it doesn’t, I might do it just in case. I really have no idea what’s happening. Have you moved the other fish to the DT? If you have how are they doing?

 

I did a chunk of research online before landing on the no planaria treatment. It’s apparently popular with shrimp breeders, but also safe for fish and beneficial bacteria.
The active ingredient is some kind of coconut derivative, but I know that just because something is natural doesn’t mean that it’s aquarium safe. I’m monitoring closely.
chromedome52 thanks for your input. I tell people this all the time, so I suppose I have to accept myself: if you’re going to ask an expert for advice, you should be prepared to hear what they have to say. Your response wasn’t what I expected, but I’ll take it under advisement and research/monitor accordingly.
I so can’t wait to tear this quarantine tank down and nuke everything in it. Although, I suppose I could keep it running for a bit after fish are moved out, feeding the tank nothing but fish food, and see what the critters on the glass develop into.

 

How many fish do you have left in the QT?

 

Seven rummy nose and one swordtail. The gold ram died two days ago (that really sucked), and the last cory today. I’d feel a lot better about moving the remaining fish over to my main tank if I could stabilize the quarantine tank for at least a few days without any deaths. I’m sort of playing it day by day right now, but I totally agree with your prior comment (and where you’re probably going now) that moving them over sooner is probably better. I just need to convince myself to actually do it.

 

I would go for it, it’s better to move them over now and risk it rather than the almost definite that they’ll get sick in this tank. There must be something in this tank that’s killing off your fish that we don’t realize and there’s quite a chance it’s just the tank. I know how you feel though. You could leave it for a couple more days but if any more fish die I would suggest moving them over.

Do you know if there was anything dropped in the tank before they started dying? Or maybe the tank was cleaned with soap that took a little while to leach from decor? I’ve been brainstorming lol.