hi had six dead today and had a dead every 3 days or so ,
Water from a lake.
shrimps and sanils inhabit the tank as well.
feed on artemia and shrimps, use to feed steamed mackerel,
Water at 28 c but since three days to now at around 30c
yesterday afternoon a lot of rain temperature drop but after the rain
Death that happened before had no rotten fins as picture so I think it is a bacteria problem,
I don t know how to deal with my biological filter.
1-isolate from filters
2-treat
3- wash pond
4- refill with lake water
5- open valve to filter and get contaminated again?

Water from a lake.
shrimps and sanils inhabit the tank as well.
feed on artemia and shrimps, use to feed steamed mackerel,
Water at 28 c but since three days to now at around 30c
yesterday afternoon a lot of rain temperature drop but after the rain
Death that happened before had no rotten fins as picture so I think it is a bacteria problem,
I don t know how to deal with my biological filter.
1-isolate from filters
2-treat
3- wash pond
4- refill with lake water
5- open valve to filter and get contaminated again?