Dying zebra danios

[Lori698]

Hi all

Need some help urgently.
I have a 54L tank unplanted with the following fish.
3 zebra danios
1 pleco
1 angelfish
1 Balashark ( very small)
2 mollies

I have a fluval filter suitable for tank and an airstone and econoline sunny 11w light.

I do regular water changes approx 10% per week and really like to look after my little guys. They get one feeding a day.

I did a water change (tap water treated with tetra aquasafe) yesterday and noticed this morning that one if the zebra danios had really bad red gills and unfortunately he had died when I came home from work this evening. He looked like he had been bleached his stripes where faded. (Will post pic)

I have lost danios before with similar situations, just don know what I am doing wrong and don't want to lose any more.

I've done an ammonia test will post pic also as it looks ok. It's light green when test finishes. Using the nutrafin ammonia test.

Help pointer what I am doing wrong or what else can I try ?
Is it a bacterial infection.

Also when cleaning should I kick up the gravel a lot ?

 

[Lori698]

Also just did a 5 in one aquarium test ( bit unsure what the correct readings should be.
But
Gh was around 120 not quite darkest blue)
Kh was around 80 light green
Ph 6 / 6.5 was very light orange
Nitrite 0 stayed off white colour
Nitrate was 80 which is high I think mid tone pink.
Is that my problem ? How should I combat that ?

Pic one ( first dip )
Pic two ( 30 seconds later)

 

[Bix22]

Ammonia looks ok , nitrates may be the culprit - to lower this, do daily larger water changes like 50% to reduce the nitrates then add properly conditioned water. A weekly 10% change is not enough, you should do at least 25% a week.
I would also recommend an API master test kit, much more accurate than strips.

 

[Lori698]

Thanks I try a 50% water change. Just nervous as the danio was fine before I did a water change

 

[aquandrew]

i dont think 10% water change is enough for the fish you have in there. the angels and pleco are going to need a bigger tank and the bala shark will need to be rehomed. when bala sharks are kept alone they get aggressive and they need a 180 gallon tank. i have a couple balloon mollies in a 20 gallon and i have to do 50% water change to keep the levels acceptable

 

[aquandrew]

also i cant remember the name of the paradite but there is one that causes gils to look red and bloody

 

[aquandrew]

parasite*