Corydoras Loxozonus Issues

[SuperGuppyGirl]

So purchased 10 loxozonus corys and am having issue after issue with them.

Tank sits at 24C (highest of their temp range), all readings are excellent (Ammonia - 0, Nitrite - 0, Nitrates - 20ppm).

Been in QT for almost 2 months, 15G long tank with 50G AC & 30G sponge, sand bottom, lightly planted, small power head to keep oxygenated and prevent dead spots collecting gunk, 2 pieces of old driftwood (no longer leech tannins), and 4 IALs.

Lost 4 corys and looking like a 5th on its way.

1st loss- aggressive form of fin rot about a week into QT, added IAL and a bit of methyl blue (3 drops per G) and upped 50% WC to twice a week. No improvement after fish died during 2 week of treatment. 75% WC after removing fish and parameters were still great.

2nd loss - 3 days after 1st fish died again with aggressive fin rot, added more IAL, started kanaplex treatment ( 3 spoons and 25% WC every other day). Cory lasted 6days. Overhauled tank as none of the others showing any signs of illness at this point. Drained tank after removing fish, scrubbed driftwood, tossed plants and substrate, tossed used media, vinegared whole tank, reset up and cycled with sponge from healthy tank. Added fish back after testing and bleached nets and sponge from sick tank.

3rd & 4th loss - 6 or 7 days after 2nd loss, noticed 2 corys with nostril issues (looked like fungus but only on nostrils, no where else and looked like they were clogged), Got aggressive, did a 75% WC and started using metroplex and paraguard together with twice a week 50% WC. Fish looked to be starting to recover as fungus was receding from around nostrils. The fungus was gone so I stopped the paraguard and was doing one more week of metroplex when within 2 days fish both passed.

Cleaned tank yet again with massive overhaul (getting tired of tossing plants and thank god playsand is cheap), recycled and tested again (yes checked my liquid test kit is not expired) and re-added corys.

Everything was fine for a solid week, thought yes beat this and came home today (1pm) to a 5th one, this one with the clogged fungus nostril and now popeye in one eye. Tested water everything is dead on (0/0/20), there is no gunk built up anywhere, they are all still eating well even the sick one but aside from eating it just lays on sand. There was no evidence of popeye/fungus on Thursday night (Friday is fast day, so no lights I leave tank dark). I do a regular maintenance every week normally 50% WC, feed a good quality breeder flake, no issues in any other tank. Someone please help as its practically killing me to lose these corys. Ive tried googling to no avail, asked at lfs but nothing. Been on internet for last 3 hours and cant find anything and just as writing this saw the cory has passed (daughter noticed her wedged in driftwood). Will post deceased pics shortly.

Edited March 5, 2016 by SuperGuppyGirl

[elf_poop]

Not that I have much exp. rescuing corys, but what about doing 10%WC every day or 25% every other day? Try salt? Boil your playground sand?

[SuperGuppyGirl]

I've replaced substrate twice to no avail. Scrubbed down everything with vinegar. Just st wits end. Never had issues like this with corys. Only thing I can think of is just poor stock

[FunkSolid]

I've replaced substrate twice to no avail. Scrubbed down everything with vinegar. Just st wits end. Never had issues like this with corys. Only thing I can think of is just poor stock

You have given it a valiant effort thats for damn sure! Using the Kana, Metro, Paraguard you have covered a lot of bases, changed water like your life depended on it, but still lost the battle. This is a touchy question, but did you buy these fish from a big chain store, local store or another AA member? Reason being that farm raised fish and antibiotic resistance are a sad reality today.

My shot in the dark guess is that you had a virulent bacteria, that was resistant to common antibiotics. You may have bought some time dosing them with metro/kana, but they probably had some resistance or other virulence factors that allowed them to kill your corys. The metro should have gone after the anaerobes and protozoans, and the Kana should have selected the Gram neg aerobic population, and thats a pretty good spread to cover. People generally associate popeye with poor water conditions but yours tested fine, so probably not the case. I would treat all remaining affected fish and equipment as "Ebola Outbreak" type quarantine, and maybe switch to bleach for any further sterilization. Some anaerobic bacteria do have a shot at surviving the vinegar depending on concentration and exposure time.

If you want to keep trying out options, Seachem has their Polyguard which has a interesting blend of antibacterial/protozoans and it would be acting on different mechanisms than the Kana/metro. It also contains Metros bigger brother that punches harder.

Those are my wild guesses that may be totally wrong, but please keep us updated. All this saved data will hopefully help someone searching in the future :-)

[SuperGuppyGirl]

Ill look for the polyguard. I have bleached the sponged and nets, if I lose anymore I'm thinking your right and will bleach the tank. I'm careful with cross contamination as have a few rarer species I'd hate to lose. Thesee came from Aquarium Central, double checked with them and they've had no deaths for awhile. Did find out they were landed in RO and they transitioned them to tap. Didn't know that earlier so just wondering if that could be a factor

[Jayba]

I would hit them with Flubendazole and RO water. This could be a water problem, in that they at a cellular level cannot tolerate the harder water.w If nothing else, it wouldn't hurt. Flubendazole is a go to for new South American fish for me. It has eleminated wasting in apistogrammas and rams I have had over the last few years.

Good luck

Edited March 8, 2016 by Jayba

[cjerrom]

Oxolonic acid works on the mystery stuff as well the metro you get from seachem is hobby grade - using pharma grade from NFP is much more concentrated and works fast. As well nitrofuracin would help in the tissue repair and can be used with metro. . Erythromycin would have probably stopped the eye issue as well but since it was only on one eye I would think it was an injury relate issue vs Popeye. I'll put some bags in the auction this weekend with enough to treat 100gallon each dose.

You'll be surprised how little it takes but it works on wild caught all the time. I treated my weitzmani and sterbai with the similar issues a few weeks back -they came in all cloudy and pissy lookeing. I used 3% salt, 78F and metro and 3 days later only 1 death out of 30 and everyone looks like a black bumblebees and orange fins with spots going everywhere now! Girls are chased around the tank with a 2-3 male posse in pursuit.

[fishclubgirl]

Girls are chased around the tank with a 2-3 male posse in pursuit.

Now that's my kind of medicine...