Help with sick Neon Tetras :(
So I got 9 Neon Tetra on Friday 29/05 and added them to my 12 day old 54L tank. Three died today 31/05. I woke up to a tetra dead in the filter and wasn't sure what happened, but I've witnessed two Tetra's decline rapidly in front of my eyes over the course of the day. They all had a white patch, became very slow and isolated themselves from the rest of the group.
Can someone please let me know if they think this is due to a bacterial fungus, or if the fish are simply stressed? It was hard to get a good photo.
They were stressed on Friday when we got them as expected, however the lights were turned off for 24 hours and we did not feed them for 24 hours. They seemed happy yesterday exploring and coming up to the front of the glass and going up and down the water filter stream. It's happened all of a sudden.
When cycling the tank I used water conditioner, a bottle of Tetra SafeStart Aquarium Starter (bacteria starter), filter running 24/07, pre-set heater running, 6 hours of light everyday, added live plants with 1ml of plant fertiliser.
I have:
- a 54L tank
- Tetra Easy Crystal Filter 250
- Tetra Pre-set Heater for Starter Line Tank
Pics attached of the fish with the white spot