Sorry to hear you lost your guy. I think the biggest thing, once they're eating prepared foods reliably,is maximizing fatty acids. Mine love brine too, but I don't use it anymore because it doesn't have enough nutrition for them. I use LRS Fertility Frenzy as their main diet. If you're not familiar with the Fertility Frenzy, it's designed for breeding clownfish. It is very high in fatty acids. I saw a noticable gain in weight after I started using it.Bad news guys. My filefish died. I'm not sure what the issue was. they were fine for months with no issues. One day one of them stopped eating and hid/latched onto the rock. 2 days later it died. and the same day the other one began the same process and also died in two days. no signs of illness or stress prior to this change. no issue with water chemistry and no changes with any other fish. They just went from ravenous, active, and fat, to reclusive and fasting. I don't think they starved it was so sudden and they weren't emaciated when they died.
I was alternating between feeding spirulina brine and Mysis in my tank. my guess is that wasn't enough variety. maybe they were willing to eat foods other than coral but their bodies still needed some nutrients they weren't getting? Maybe they were collected with cyanide? I've heard that fish collected that way can seem healthy then suddenly succumb to organ failure as a result of exposure months earlier?
I was so proud of my fish I didn't want to announce to the forum that I failed in my husbandry. I've seen more filefish showing up at my LFS that eat prepared foods from time to time but I know I can't justify adding another pair to my tank without knowing what I need to do differently to care for them.
But this has revived my interest in these fish. I miss their beautiful colors and inquisitive personality and would love to keep them again. Does anyone think they can help me figure out where I went wrong? I really thought I had orange-spotted filefish figured out. It was great for about 3.5 months then the suddenly seemed to lose the will to live. Not for lack of trying but I know it's my fault I let them die. I just don't know what I did wrong?