hey sorry for your loss mate , they really do hate large changes to there water , i lost my reds at less than 50% change trickled in via ro and carbon block.
let me ask you a favor though , have you still got the fish ? if so can you please take a picture of the teeth for me and post it up , i can then get a picture of marulia teeth which are totally diferant ,so we can have a guide for telling them apart when in juvie stages ,as there is a lot comming into the trade at the moment that look very much mauraloides but on inspection of teeth have been found to be marulia
many thanks col