Oto with pink patch

[diggozo]

In my 55 gal tank I have four Otocinclus (first time for me) who have been in the tank for just over one month.

Three of them are looking v.good but the fourth and biggest has developed pink patches over its head. It has an excellent appetite and still rushes around like greased lightning.

The tank water is AOK but the temperature has been around 84/86 which suits my Angelfish but I wonder if it might be this that is causing the Oto's problem.

The weather is now beginning to cool and I will then hold the temp to 79/80 . . has anyone any ideas about the effect of high temps on Otos ?

 

[Blinky]

Is there any way you could post a picture? That would really help. In the meantime, you could try searching for 'hole in the head disease' on Google and see if that looks like what your oto has developed. I've only ever heard of cichlids getting the condition but when you said he's got circular patches on his head, it was the first thing I thought of - it can occur from vitamin deficiencies. I've read that whether or not it's caused by (or related in any way to) Hexamita (intestinal flagellates) is up for debate, but almost everyone agrees that vitamins in the affected fish's diet can help reverse the condition. If that's not what he's got, can you get a picture or give a really detailed description of the spots and list your tank specs and water parameters?
I've always kept my otos at around 80F, I'm not sure whether having them at 84+ would stress them a lot or not. If all the others are fine I'd say it's probably not directly related to the temperature, but if they're slightly stressed by it an infection could find it easier to take hold.

 

[diggozo]

My tank is 55 gals inhabitated by six small Angels, three small Peppered Corys, four Otos and a smattering of Guppies - planted and with a great deal of bog wood to help soften the water.

The readings on Wednesday 31st were

N03 < 10 , N02 0, NH3 < 0.1, dGH 10, dKH 3, pH 7.4 , Temp 84 and I do a 6 litre (1.5 approx) gallon water change every day without fail - 20% approx per week.

No it is nothing like 'hole in the head' it is rather like a pink skull cap extending from the pectoral fin on one side over the head and down to the other. It originally started on on one side but has now extended itself. It does not seem to affect the gills. Have studied it through a magnifying glass and can see no signs of raw tissue although it is difficult to be certain through the glass wall. It is perhaps rather similar in looks to a bad burn scar on human tissue.

As I said he has a good appetite and displays no signs of stress. The other three Otos are fine. One interesting point is that the four Otos were all the same size when I bought them but this one grew at an amazing rate and is now a good third bigger than the others - maybe it is a mutant . . "The Gozoto".

There is a not a great deal of algae in the tank so I feed them TetraTabiMin and TetraPlecomin Tablets to supplement their diet and which the Silver Angels go wild about ! !

Sorry . . I can't produce a photo and short of dismantling the tank so that I can catch the slippery little chap there is no way of getting a closer look.

My concern, of course, is that whatever is causing this disfigurement does not spread to the other Otos . . . they are such cute little buggers that I would not like to lose them so early in their life in my tank.