Severum - Red Growth Eating Tail Away

Hi Guys,

I've joined up to get some help, as I have been trying to work out what on earth my Gold Severum has. There are red growths on his tail, which when they die off, take the tail section with it. he's got a half a tail left as per the photos. The growths are slighly bulbous, so they aren't just "in" the tail, they are "on" it, if you know what I mean.

extensive google searching has so far not helped, so I've joined to get it from the experts. can anyone please let me know what the problem is. The growths started about a year ago, and came and went, taking a bit of tail each time. I used some multicure, which seemed to speed up the process, but it always came back. I was advised by the local pet store to try Melafix, but that was an expensive waste of time, as it did nothing. The red growths (which are also accompanied by red striping up to his body) have now been there for some time without "coming and going".

I have one other severum, and a few tetras in the tank, and none of the other fish are affected. Water is changed regularly, gravel is vacuumed regularly. He moves, breathes and eats as if it's not even there, so it's not making him visibly sick.

any advice is greatly appreciated, as I would not like to see him lose what little tail he has left. I'm fairly new to fish tanks, so "dummy advice" is appreciated, as I probably won't know what you're talking about if you start throwing fancy names for medication at me.

cheers,
Nathan.

That's most likely blood from the damaged rays. Which other stock do you have in the tank? Water parameters? How large are your water changes and how often do you do them?

My recommendation is that you treat with a generic anti-fungal/anti-bacterial medication (like eSHa 2000) and improve water quality or find the culprit.

tanks is only stocked with the gold severum, one green severum, 3 scissortails, 3 columbian tetras and about 8 neons. water changes are 33-50%, once a fortnight (4 ft tank). I don't test nitrates or ammonia levels, only PH once a week.

I'll try and find a better multicure.. the one I've used is the off the shelf variety from the supermarket and the local pet store. I might try my local aquarium and see what they've got.

Have you ever seen the fish fight? Now is a good time to take your water to be tested at the LFS for everything: ammonia, nitrite, nitrate, KH and GH. If the fish have never fought, one of those is most likely to explain the tail.

If possible, a 30-40% water change per week would be better then once every other week. Also, it would be useful to know your tap water KH, GH and pH readings (also ammonia, nitrite and nitrate after dechlorination too).

Unfortunately, pH on its own is not particularly useful. For example, this morning, I tested two of my tanks, both of which get tap water water changes and top-ups, tank A had pH of 8.0, KH of 6° and GH of 16°; tank B had a pH of 8.2, KH of 9.5° and GH of 21°. The pH in B was only 0.2 points higher (which is still not a what we normally consider a big difference, although the difference is high) than in A, while the KH was almost 60% higher and GH around 31% higher, both of which are enough of a difference to shock the fish if it was moved directly from one tank to the other. My tap water readings are different again from these. The point is that a large water change (50%, for example) with different water is enough to stress the fish so much that it picks up fin rot.