Zebra Danio Help Please!

[karlosbaby]

Hi all, i am currently in the process of stocking a 40 gallon tank. I started with 5 zebra danios 4 female and 1 male.
after adding 3 peppered cory's and 2 panda corys last week and 2 otos this week, I found one of my female danios had completely vanished.

not only had one vanished, one of the other females seems to have taken some damage to its tailfin

i have searched my tank and cannot find this missing zebra, could it be that the other danios have all attacked it and possibly eaten it??

i know it sounds like a crazy idea, but i really cannot think of anything else.

I have checked all the plants, and in the filter.

P.S this all happened in a space of 2 maybe 3 hours today

 

[WILDER]

Have you checked around the floor area.

 

[karlosbaby]

yer i have looked everywhere, next to taking everything out i have done everything

 

[WILDER]

I think I would take everything out of the tank.
It easy to look for fish then.

 

[karlosbaby]

well i have a day off tomorro so i shall try to ge as much out as i can.

but its really odd how for two and a half weeks they have all got along fine and then within the space of 3 hours one has vanished and another has damage to its fins

bizzarre

 

[WILDER]

If you can't find the fish it been eaten, or died and they have eaten it.
Have you looked round the back of the tank.

 

[karlosbaby]

yer i've looked in the tank, under the tank, round the back of the tank and even in the cabinet as it has an open back

 

[WILDER]

It sounds like the fish has been eaten them.
How long did you climatise the new fish for.
What are your water stats in ammonia, nitrite, nitrate, and ph.

 

[karlosbaby]

ammonia is less than 0.25ppm just above zero due to puting some otos in this morning
nitrate is 5
nitrite is 0

 

[WILDER]

How long has the tank been set up.
Don't add anymore fish to the tanks cycled.
Otos are very sensitive to water quality.

Shouldn't of added the corys either as there senstitive to water quality.
Not many fish tolerate a cycling tank.

 

[karlosbaby]

the tank was cycling for four weeks without fish, just by adding a small amount of food, and then added the danios at the end of week 3.
added the cory's at the end of week 4 and the otos this morning

 

[WILDER]

What's your tap nitrate reading.
The tanks gone into a mini cycle with adding new fish.
I would wait till the ammonia and nitrite reading are at stable 0 reading., before adding anymore fish.

 

[karlosbaby]

ok thanks for the advice, will update tomorro if i find the missing danio

 

[WILDER]

If you add the new otos you could lose them.
Hope you find the missing fish.
Good Luck.

 

[karlosbaby]

well, luckily i have found my zebra danio

the panic qnd worry came when a second one vanished so i instantly took 25% of the water out,

and then something came into my head, no idea how....
i have....... had an artificial moss ball in my tank near the bubble pump and filter,

inside of this i found two zebra danios

but they have sort of turned black on the upper part of their body and it looks as though scales have been damage

is it best to try and treat them with something like mellafix or should i just put them out of their misery??

please let me know as soon as possible guys