For about 2 weeks now my tetras have been slowly dying off. One will dye then the next one will go after 2-3 days. So far I have lost 3 neon tetras and 2 glowlights.
Usually they are all fine at night and then one will be dead and stuck to the filter intake in the morning. The neons all died first. The glowlights seem to be in respiratory distress for the day preceding their death. The last fish that died was laying on its side breathing very rapidly and constantly flapping its pectoral fins, with an occasional partial tail twitch for the entire day before it died. The vein going down its spine was very red, its gills were bright red and a bit curled/crinkled outwards.

Tank size :10 gals
temp: usually 79-82 degrees (depends on how hot it is outside)
Ammonia:0
Nitrite:0
Nitrate: 10 or less
ph: 7.2-7.4
Tank has been established about 8 months
Original stocking: 5 neon tetras, 5 glowlight tetras, 2 albino corydoras, 1 adf
Remaining: 2 neons, 3 glowlights, both corydoras and the frog

I know that the stocking levels were a tad high, but the whole tank produced 5-7 ppm of nitrate a week.
So far the corydoras and the frog seem unneffected. There were no outward signs of illness in the neons, and just the last glowlight had the really red veins and curled gillflaps. All of the fish were bought and added to the tank at the same time, no new fish since then. Nothing new has been added to the tank either. The tank has about 1/2 inch of gravel for a substrate and a few live plants in it. The lights are usually on for 10-12 hours a day. I have not treated with anything because I have no idea what is wrong at the moment.

Anyone have an idea what could be wrong with the fish/tank?

I've had similar things happen in established tanks. Tetras can be a real problem like that, everything seems healthy and then all of a sudden they begin to die off, and my cories also seem unaffected during all of this. I won't guess at what exactly it may be, but my best suggestion would be to buy a good antibiotic treatment and dose the tank (make sure it's safe for your frog first though!!)

Chrissy

I have melafix, triple sulfa (which I think is out because of the salts), and maracyn 2. I am hesitant to just dose the tank without having any idea what is going on. Whatever I need to do will have to be finished in about a week because next weekend I am leaving for a week and my grandma is gonna have to feed all the tanks. I don't want to get into a treatment cycle where they might need a second run and have no time to do that.

Well, whatever it is the melafix is very likey too weak. Take it from me, I had a very similar situation recently (you can probbly search and find my posts) and I tried using just melafix in an effort to keep my cycle intact, and the fish just kept dying. I finally broke down and used tetracyclen and my problems stopped. I know it's frustrating not knowing what's causing it but it can be very hard to determine. As you said the sulfa is out but I think maracyn may be a good idea. If you started it now you'd likey be done in time for next week too, most meds I've used have had a one week cycle. I'm not too familar with maracyn though, is it antibacterial?

Chrissy

Maracyn is an antibiotic. Supposedly it might not completely crash the cycle, however I will have to remove all my filter media anyways because the type of filter thats on that tank. Its bacteria farm/filter floss is in a cartridge with carbon in the middle. No way to pull the carbon without crashing the cycle too.

I also am worried about the remaining tetras because there is no longer enough of either type for their schools/shoals. For the most part the 5 left are all schooling together but about 10% of the time I look the neons will be in a completely different side of the tank from the glowlights.

If the meds are safe for the frog would they be safe for the cories too?

Neon Tetra Disease?

If the meds are safe for the frog the cories shoudl be fine. The tetras will be a little more stressed with lower numbers, but if they have hiding places they will be ok until you are able to restock your tank.



That's what I was thinking, I figured that's what hit my tank a few months ago and it sounds the same as what's going on here. For me the meds finally stopped it, hopefully the same will go for you!

Chrissy

Can that spread to other types of tetras?

I read the booklet on different treatments for fish. It does not say if maracyn 2 is safe for the frog. It does not specifically say that it might be dangerous to some aquaruim residents like some of the other treatments do. I also have maroxy which I dodn't mention earlier because I thought it was just an antifungal. But, according to the booklet it has had some success against certain tyes of both gram positive and gram negative bacteria. Wheras maracyn two is primarily effective against gram negative bacteria, but works against more of them that fall into that category.

Anyone ever treat a tank with a frog in it with either of these?

that happened with 2 of my tigerbarbs, they both died a day within each other

Sorry to hear about your tetras. I don't know what is wrong with them, but you had some questions about neon tetra disease, so here is a couple of sites for you to reference:

http://www.aquahobby.com/gallery/e_Neon_Te...odon_innesi.php

http://en.wikipedia.org/wiki/Neon_tetra (scroll down to disease)

Everything I have read says that if it is NTD, to euthinize the effected fish and clean you r tank to keep the healthy fish healthy. The spores (I don't remeber exactly) float around inthe water and are eaten by the other neons who then become infected. No sites I have found say whether other fish cancatch it, sorry, but you could do a larger web search.

God luck!

OOPs, sorry about the double post, I was having trouble editing it, but this post has a different web link for the second one, I thought it was more helpful than the one I was trying to edit (I am blushing).

Sorry to hear about your tetras. I don't know what is wrong with them, but you had some questions about neon tetra disease, so here is a couple of sites for you to reference:

http://www.aquahobby.com/gallery/e_Neon_Te...odon_innesi.php[/url] (info. specifically about NTD)

http://www.tropicalfishcentre.co.uk/Diseases1.htm (this is a diagnosis chart)


Everything I have read says that if it is NTD, to euthinize the effected fish and clean your tank to keep the healthy fish healthy. The spores (I don't remeber exactly what they are) float around in the water and are eaten by the other neons who then become infected. No sites I have found say whether other fish can catch it, sorry, but you could do a larger web search.

Good luck!