This must be a nightmare,please help

[portisheader]

Hello,
I have 4 mollies and their juveniles,3 red fin sharks,4 platies in my 125 tank .I measure water parameters once a week.Yesterday morning, nitrite ammonium readings were almost zero,the nitrate level was too high.So I immeadiately changed 25 lt of water.I use some test strips with color scale for testing.After I changed the water,the nitrate level seemed to drop .
This morning it was terrible to see two of my juvenile black mollies lost their left eyeball.
The eyeballs are simply gone,it is like a horror film,there is no wound,scratch or blood around the eye,the only thing I recognized is that the skin changed to white between dorsal fin and the eye...

Now they are swimming like a fool,it is a terrible scene.

I need help,is it nitrate that caused this nightmare.
Ineed your help ,what to do now with the others,with my single-eyed mollies.

thank you
portisheader

 

[bigfish]

red tail sharks attacked them in the night?

 

[suemack]

RT sharks was my first thought too - have they been in the tank with the other fish for very long?

 

[portisheader]

bigfish,suemack,

It's been more than 1 month since I put the sharks in the tank.During the day sharks only chase each other,I've never seen they disturb mollies and platies ,even when I feed them,mollies and platies are more dominant than the sharks.
If this is the case you suspect,I may isolate sharks
thank you
portisheader