Fry mortality

[mummymonkey]

Came home from work to find a number of dead fry in one of my tanks. Some fry were alive but clearly about to expire. All had the same symptom; a large tuft of fungus growing from their gills. Here is a picture of a live fry with the fungus growing on it:



The dead fish had fungus tufts of over 1cm long! Pretty freaky to see actually. They were okay at lunch time but in this state only 8 hours later. Only one tank is affected thankfully. The water tests okay for ammonia etc but I've done a 50% water change anyway (using water from another tank).

Anybody any ideas?

[Coryman]

I don't want to be a bore, but have you read the sticky at the head of this forum. Some basic information would help a lot.

One question, well two actually, How often do you make water changes in the fry tank and by how much?

Ian

[mummymonkey]

Sorry Ian, getting a bit ahead of myself.

1. Water parameters
a) Temerature range. 75F
b) pH. 6.8
c) GH. 2
d) KH 1
e)Ammonia, Nitrate, Nitrite, levels. 0,<10,0
f) Water change frequency 2 x weekly of 30%

2. Tank set up
a) Size. 18x12x12
b) Substrate. recently added thin layer of sand
c) Filtration. corner box filter
d) Furnishings. ceramic bowls & coconut shells
e) Other tank mates. none
f) How long has it been set-up? 2 months in present configuration. Filter was mature from start.

3. Symptoms / Problem description As previous post

4. Action taken 50% water change

5. Medications used none

I have 4 tanks set up like this plus 1 36x12x12 with older fry. Around 160-180 fry all together. No further deaths today. I had done a water change the night before with day old water as usual. The tank pH of 6.8 is a little lower than normal, this may be because I used water from the 3ft tank to do the 50% water change with yesterday. Generally it's bang on 7.0.

Here is a picture to give you an idea of the setup.


Thanks for your time, I appreciate it.

[Graeme]

My first thoughts are the newly added sand with such small specimens.