New Cory Sick

[LauraFrog]

I bought two pygmy corys (habrosus) two days ago. They were in the bag for less than two hours, with oxygen and ammo-locked, and appeared to settle in well, they were eating the first night I had them home.

I put them in a planted 6 gal. It was set up six months ago using cycled media and a heap of platy fry. The platy fry are now almost fully grown (resulting in a hugely overstocked tank with no problems other than the nitrate being high, 50% WC/week). So I shifted out 3/4 of the platys and did a big water change, then I added the corys. And like I said they settled in well. The only problem I've had with that tank is black beard algae.

I didn't see the corys at all yesterday because I got flooded out. I had my mum put a piece of food (Hikari algae wafer) in there for them, but it could have been eaten by the platys.

I just checked on them and oh boy... I have no idea what's wrong. I saw one of them briefly under a piece of wood, nowhere near as active as it was but looking okay. The other is corkscrewing all over the tank and resting upside down on objects. It looks like it's dying and I have no idea why. Water params taken about five minutes ago are temp 25C, NH3 negative, NO2 negative, NO3 20ppm, pH 6.8-7, which are all normal for the tank and I can't imagine why this cory is practically dead.

Can anybody help me? this is a rare fish in Australia and I really don't want to lose it, not least because of what I paid for it. There are no external symptoms at all other than its apparent lack of balance and lethargy - no sores, no lesions, no slime, fungus, fin damage, nothing at all. I don't know for sure if there is anything wrong with the other one.

Thanks!

 

[LauraFrog]

I read that this can be caused by water contamination or a bacterial infection, and it makes sense that either would affect sensitive pygmy corys and not extremely tough bush-raised platys. I did a 50% water change and dosed with melafix. I'm not certain that this is bacterial. I have tetracycline on hand but I don't really want to move them and I don't have another cycled FW tank if the tetracycline kills the cycle in that one.

EDIT: There may be a slight improvement after the above. I'm not sure yet. If they improve further I will change more of the water and redose melafix.

 

[WILDER]

Sure it black bearded algae and not that terrible bacteria that turn the sand black.
What substrate do you use.
Cork screwing can be internal parasites to bacterial.
Dosn't sound good has he died yet.

 

[LauraFrog]

Both of the corys are still alive... at this point it seems like only one of them is affected, the other seems normal but when its companion takes off on a whild whirl around the tank, it follows and seems fairly distressed.
He seems to be corkscrewing less, just swimming extremely fast, but he often loses balance and falls onto something, or flips onto his side and then back up while swimming... it's certainly not normal behavior, and when he's not doing that, he's resting, often lying on his side or even his back. There doesn't seem to be any change, he doesn't look any better or any worse really.

The substrate is sand, it's definitely black beard algae. there is none on the sand, it's all over the leaves of the anubias, and there is some on the wood and rocks. It's extremely annoying because it grows on the leaves and on the front glass.

I just realised I left carbon in the filter so there's no melafix in there... but wouldn't running carbon rule out contaminated water? Should I do another water change?

 

[WILDER]

I think its bacterial or internal parasites.
Fish can act wierd when there dying, like darting, whirling, turning upside down.
Cork screwing motion can also be a sign of internal parasites.

 

[Colin_T]

Corkscrewing and spiralling through the water is either bacterial or protozoan. It is often caused by dirty tanks. You mention you have done water changes but have you cleaned the gravel/ sand and filter? If they haven't been done in a while then they could be filthy and that would encourage disease organisms to thrive.
Platies are dirty fish (as are all livebearers) and they were probably fine. But the cories don't like dirty tanks and if they had come from a nice clean tank and gone into a dirty one (dirty gravel anyway) it might have been too much for them and one has developed an infection.
Try doing daily water changes and gravel cleans and make sure the filter is clean. You can add some melafix if you want and it might help.

The carbon will only absorb chemicals until it is full then it won't absorb any more. You are better off leaving carbon out of the filter until you need it to remove chemicals. Then you can add it to the filter for a week before chucking it out.

Cut back on feeding because the fish won't eat much if they are ill.

 

[LauraFrog]

The carbon was in there because I'd run some praziquantel before I put the corys in as I know platys often carry parasites without being affected. If the problem is parasitic, the cory already had it before I brought him home. (Or else it doesn't respond to prazi, in which case I'm screwed.) I'll chuck the carbon as it's probably loaded, the water still tastes like melafix. I did clean the filter before I put the corys in, it's about 50/50 floss/bio-ceramics and I changed about half of the floss and rinsed the rest before I put the corys in the tank. I siphoned any obvious gunk off the sand, but it's too fine to put a gravel cleaner through it - is there anything else I can do to it? Basically since it's been in there all I've done to it is syphoning off the fish poo and gunk sitting on it whenever I've done a water change. From looking at the sand pressed against the glass, there doesn't appear to be gunk between the grains.

The sick one is still alive, last night he was swimming too fast and resting in awkward positions (including totally upside down) but not corkscrewing. This morning he's back to it again. There has been practically no change in his condition since I noticed he was sick.

I've got both praziquantel and tetracycline on hand. I can get Sterazin, Myxazin or Protozin but they'll take a week to get here. I've got a very cheap generic whitespot med (methylene blue/formaldehyde) and a very cheap generic multi cure (methylene blue/malachite green/acriflavine). The instructions for using them are very poor and I think I keep overdosing whenever I use them. In any case, I used them when I had no antibiotics and I always ended up killing the fish in question. They are both out of date, I bought them when I started fishkeeping and I didn't realise they were largely useless. Obviously, I've got melafix. I've got salt. Increasing the temperature is no problem, but lowering it's not, as it's summer in Australia and the room temperature doesn't drop below about 24C.

My other FW 'tanks' are all plastic containers that I raise livebearer fry in and because I can't filter them, I just use ammo-lock and do frequent 90% water changes. So if I did manage to wipe out the cycle putting tetracycline in that tank, I've got nowhere to put them because my cycled tanks are all brackish. I don't like the chances of keeping pygmy corys alive for four weeks while I did a fishless cycle on that tank...

If I did treat with antibiotics, could I remove the cycled filter media from that tank and run it in one of the fry raisers? Would that keep it cycled (and I could just run floss in the box while tetracycline was in there and use ammo-lock)?

 

[Colin_T]

Praziquantel only treats tapeworm and flukes. It does nothing to protozoan parasites.
The easiest way to get rid of chemicals in the water is to do a couple of big (50-75%) water changes. This will dilute the medication and you won't need carbon, or if you do use carbon, it won't block up as quickly.

You could stir the sand up. Carefully drag your fingers through it and that will loosen it up and help lift any gunk out of it. Then after it settles you can syphon the gunk off the top. Alternatively kink the syphon hose when you gravel clean it. That will slow the water flow down and allow you to clean the sand.

I wouldn't use Tetracycline as it is a strong antibiotic and should only be used as a last resort.
Sterazin and myxazin probably won't work, whereas Protozin should but it contains similar ingredients to the cheap generic medications you have. Namely formaldehyde, malachite green, methylene blue & copper sulphate.
Methylene blue, malachite green and formaldehyde will kill most fish diseases and you could try using one of the old medications, probably the multi-cure. Only use them at half strength for catfish.

To work out the volume of water in the tank
measure Length x Width x Height in cm
divide by 1000
equals volume in litres

When measuring the height, measure from the top of the gravel to the top of the water level. If you have big rocks or driftwood in the tank, remove them before measuring the height.

Medications & chemical test kits will last longer if they are kept cool. I keep my fish testing gear in a sealed plastic bucket in the bottom of the fridge. If you have children in the house then make sure they can't get into the bucket with the chemicals.

Don't raise the temperature because it will just speed up the disease.

Melafix is unlikely to bring about a cure on its own but might help. I would advise against tasting aquarium water due to the disease organisms that live in it. You could easily pick up something. Also if there is any residual chemical in the water (mainly malachite green) then that can poison you. Malachite green is a known carcinogen and extreme care should be used when handling medications containing this stuff.

Salt is unlikely to bring about a cure in Corydoras as they don't really like salt. Quite often the salt treatment will kill them before the disease does. A very low dose of salt won't hurt them but won't do anything to the disease.

If you treat the tank with Tetracycline the established filter should be moved to another tank with similar water parameters. Leave it running here until you have finished the course of anti-biotics.
Tetracycline should be treated each day (preferably in a bare tank) and a 90% water change should be done each day before you re-treat the tank. You should continue treatment for 5-7 days. Then do a couple more big water changes to dilute the drug before putting the old filter back in the tank.
Ammo lock isn’t normally necessary if you only have a couple of small fish and you change the water each day.
However, only use the Tetracycline as a last resort and try the other medications first. Tetracycline is a common anti-biotic and should not be used willy nilly. It should only be used when absolutely necessary. And this problem is more likely to be protozoan rather than bacterial.

 

[LauraFrog]

The Multi cure is definitely dodgy, so I might try and get one that's got copper sulfate in it. I can get protozin but I don't want to risk it taking a week to get here. I'll check what the LFS has tomorrow and if they haven't got anything I can use, I'll use the multi cure. It is very old, and hasn't been kept in the fridge. (The melafix, tetracycline and praziquantel are in the fridge).

I keep the tetracycline around because there is an awful lot of columnaris round here, I keep getting it through the water supply again and again, and if I'm on it as soon as the symptoms appear, treating with tetracycline, it usually goes away. I don't use it too often, but I like to keep a supply on hand. The prazi I use every few months in all my livebearer tanks because I add new fish frequently and usually end up with intestinal parasites.

I can't really measure the dimensions because the tank is panoramic, I know the total theoretical capacity but it's heavily decorated. If I do treat, I'll probably set up another tank with ammo-lock because the multi cure is a filter killer too, been there done that. I ammo-lock everything, it's probably just paranoia.. i've got a couple of litres of it hanging around usually because my bettas are in unfiltered tanks of about 2 gallons, and if I use ammo-lock I can get away with changing the water once a week.

I'll put up the concentrations and recommended dosages of the medication.

 

[Colin_T]

Tetracycline and Praziquantel should be kept really dry and if you have them in the fridge make sure they are kept in an airtight container and maybe add a couple of the dry packs to absorb any moisture that might get in there.

You shouldn't get Columnaris from the water supply if it is mains water. There should be sufficient chlorine/ chloramine in the tap water to kill stuff like that off. Also if there was Columnaris in the water supply then the water supply is contaminated and needs checking by the health department.

Increasing the hardness of the water can help limit the Columnaris as can keeping salt in the water. Livebearers will tolerate salt without any problems and if you salt up all you tanks/ containers with them in, keep the salt levels high for a month, and then slowly dilute the salt out, you should be able to get rid of the disease completely. Then just quarantine any new fish and if necessary treat them before they go in with your other fish.

Once the fish & tanks are clean they should not develop any new diseases unless the disease organism is re-introduced via contaminated fish, plants or live food.

 

[LauraFrog]

The problem is that it's not mains water. We can't get it here. It comes out of the creek and nobody checks it because it isn't listed as potable. It's never killed me and I've drunk the stuff for the best part of fifteen years, but you do get the odd fish disease from it. Columnaris keeps cropping up in it. The livebearer tanks are all hard brackish except for the fry tanks, I don't like to raise fry brackish because they sometimes have difficulty adapting to soft freshwater afterwards, which is what the LFS sells them for, and I don't like to pass on fish that may have a poor survival rate in other people's tanks.

The meds are in airtight containers with silicone sachets and floss jammed in the air space.

The cory is still alive, he's doing less corkscrewing/wild swimming and more lying on his side. I'm scared to risk the multi-cure because it's extremely dodgy. The instructions are 'dose the tank with x mL/20 litres. After 2 days, do a 25% water change and repeat the dose'. What I've done before is do the water change and then repeat with enough for the entire water volume, usually resulting in the death of the fish. Should I only be dosing for the 25%? I have no idea, because the instructions are extremely vague.

I might wait until tomorrow and see if I can get a better med. I'm scared to use it.

 

[Colin_T]

Normally when you treat with medications like Multi-cure you re-treat the entire volume of water in the tank after you do the water change. I usually try to do a bigger water change before re-treating the tank. I will do a 50-75% water change and then re-dose the tank at the same amount as was originally used.
Having said all that if the cory is looking a bit better today and you haven't added any medication (besides the melafix) then leave it for another day and see how it looks. The fewer chemicals you add to the tank the better it will be for the fish and you might be able to get a cure without using the multi-cure or anything else.

 

[LauraFrog]

TBH it looks the same... I will do a big water change and thoroughly clean the tank and redose melafix, and if that produces no improvement I'm going to have to pull out the multi cure... I just don't like the idea. I have never had a fish treated with the stuff survive.

 

[Colin_T]

If you lose fish whenever you use the multi-cure you are probably overdosing with it. It doesn't take much and is easy enough to do.

You probably know how to work out the volume but I will post it anyway.

To work out the volume of water in the tank
measure Length x Width x Height in cm
divide by 1000
equals volume in litres

When measuring the height, measure from the top of the gravel to the top of the water level. If you have big rocks or driftwood in the tank, remove them before measuring the height.

When treating catfish, loaches and eels only use the medication at half strength and increase the surface turbulence.

 

[LauraFrog]

I just spent a few hours practically sterilising the tank. Drained half a bucketful of water, put all the fish in the bucket. Took out all the wood, rock and plants. Swirled the sand around. Drained the tank. Poured in a gallon of water, rinsed the sand again, drained out the water. Poured in a gallon of warm water (about blood heat), swirled the sand around, drained it out. Then a gallon of hot water. Left it sit for a few minutes. Swirled it around, emptied it. Two more rinses with cold water to get the sand back to a normal temperature. Then I put a gallon of water in with the dose of melafix for the entire tank (so six times the recommended amount of melafix) and left it sit for half an hour. While I was waiting, I cleaned out the filter again, replaced the easily replaceable floss, rinsed the bio-ceramics, rinsed the pad thoroughly and put it back.

Read as: there are no bad bacteria in that flipping tank.

I took the opportunity of having everything out to paint the anubias leaves and some of the wood in raw simazine to try and get rid of the BBA. I scrubbed it all off the glass, which took me about twenty minutes. It's revolting and it's everywhere. Grrr.
Then I replanted, redecorated, refilled, turned everything back on and put the corys back in. It's just the corys, because I don't trust the filter with the platys in there as well, I cleaned it too well. The last thing the corys need is an ammonia spike on top of whatever has made this one sick.

No visible improvement yet but it's only been a few hours, so I'll keep you posted. If there's no improvement by the time I go into town tomorrow, I'll try and get a decent med.