Hi guys, I've had a batch of (at the start) about 25 Borelli fry (20 now). They are from 2 batches (1 & 1.5 mths) that I received from a friend a fortnight ago. They are housed in a 10-gallon tank that has some hornwort, a strong sponge filter with ADA Amazonia soil as a substrate. About weekly, I noticed that I was getting losses of between 1-2 fry a week. They would sit on the bottom and slowly become more lethargic over the following days, refusing to eat, tilting to one side and gliding over the substrate with a tail-heavy shimmy. When they died days later, they were relatively skinny. The other fry don't show any symptoms and look robust and healthy. I do weekly 50% water changes and feed them twice a day: once with live BBS and another with Dr Bassleer's M Pellets. My water parameters show no Nitrites nor Nitrates. PH is around 6.5 and temp fluctuates between 25/26C to 28C. I use aquarium salt 1 tblspn per 10 gal and I squirt my BBS straight into the tank. My water changes don't contain salt, however, to account for the change in salinity. I notice that the fry dying are almost always the younger fry from the 1-month batch. The largest fish (2.3cm) in the tank is more than 2 times the size of the smallest (>1cm). However, I'm not seeing much aggression (the tank sits on my work desk) aside from the usual flaring and chasing. The only other tankmate is an unidentified snail that came in the hornwort that I tolerate on the grounds that it helps to clean up the detritus. Does anyone have any advice/experience with this?