Has anyone kept Panda garra (Flavatra) fish for any meaningful amount of time in <0.5/1dKH? I have lost half the population in a matter of 1 month. It seems to coincide with the changing of all my filter cartridges including the RO membrane which is the one taking care of KH. All other fish (rasboras, tetras neons, flying foxes and ottos) are doing just fine including all shrimps. I have not noted any disease on them and they seem to be eating just fine so I really have no clue what is happening. I won't detail all other water parameters as they are all in check. 60% WC weekly. Water is pristine with a TDS of ~210ppm by week end. APT E dosed, remin at Ca:Mg ~ 20ppm:6.67ppm. (~3:1) so far.