Columbian Tetras dying HELP PLEASE!!

I have a real problem with my shoal of Columbian tetras. 1 Died about 3 months ago from some condition I'd never seen before. It lost all its colour & almost became see through, it developed black patches around its head & flanks & its mouth looked as though it had been smashed in, it died fairly quickly but none of the others seemed to have been infected & all seemed healthy until about a week ago when another of them has started displaying the same symptoms. Has anybody seen anything like this before or have any ideas what it could be? My thought is it's something parasitic but I don't know what.

Can anybody help??

Hi commando, black patches are usually a sign of a pretty nasty bacterial infection, where the skin is damaged from inside out. How long has your tank been running? newly established tanks can have all sorts of spikes of bacteria. I would suggest a strong antibacterial medication, such as myxazin or esha 2000 (esha 2000 is expensive but it covers a very wide range of infections) also do a 10% daily water change. 3 months between the first death to another showing symptoms is quite a while so most likely all are affected by it so treat the whole tank rather than move the affected one to a hospital tank.

Hope this helps

Hey Dad!
Star, the tank has been set up for 3 years now, so it's a mature tank. There's a load of shrimp in that tank, would myxazin or esha 2000 be safe for them?

ah no myxazin & esha will kill shrimp unfortunately. Bet option then is to do daily wc on the main tank and if possible move the tetra to a hospital tank and give them a course of myxazin or esha 2000.

Has the water been tested? sometimes ammonia burns will show up as black patches, never heard of it affecting the mouth though, might be worth checking the water stats also.

Hi, Just bought a brand new API test kit & checked my water parameters, they are:
Ammonia 0 ppm
Ph 7.5
Nitrite 0 ppm
Nitrate 5 ppm

All seems good, except I know the Ph is a bit high for fish like Tetras, but I have Cardinals, Glowlights, Ambers & Platinums all in the same tank & this thing is only affecting the Colombians. The weirdest bit is the mouth parts, it really looks as though something is eating them away although the fish is still eating when I feed.

I have good external filter setup which is fully mature & has a good flow rate & the tank is heavily planted, so I'm really stumped as to what this is??????????

Sounds like its a bacterial problem, which unfortunately cannot be tested for. As it seems advanced and the columbians have it worse, I would recommend a daily water change and either myxazin, esha 2000 or dose with aquarium salt. Columnaris, is the common name for this type of bacterial problem, it is present in all tanks but can sometimes just manifest itself. Do the columbians tend to squabble amongst themselves more than the others? if so this is why they have it "worse" than the others as they are stressing themselves out. Also try only turning the lights on at feeding time, darkness will help with the stress, you can also try a product called vitazin, its great stuff you soak the fish food in it and it adds extra vitamins to the fish helping them fight infection.

Hope this helps

Thanks Star, the colombians do chase each other around a bit but nothing serious. I'll give the vitazin & darkness a go & see what happens.

And lots of water changes . Most cases of this sort of bacterial problem is down to water quality, however stress is a big part and tetra being little devils can cause each other a fair amount of stress.

Just though I'd post a quick update of how the tetras are, as dad is crazy busy with work atm.

They seem to have improved - the one with the marks is eating well and is even showing more colour again, so fingers crossed it'll pick up even more.

So looks like it's on the mend

Brilliant news