ivan_dalmatia
Aquarium Advice FINatic
What's the best way for treating HLLE?
There is no definitive cause, so there is no definitive cure. Potential causes have ranged from improper diet, chronic stress, poor water quality, exposure to copper, stray voltage and using activated carbon in filtration. Its a pretty wide spread of causes.
In my experience and observations, it seems to appear most frequently with chronic stress...usually too many fish and/or fish in tanks that are too small or due to poor diet.
In your case, the "too many fish" could be a cause. You have a lot of fish in your tank and many are in there that should be in larger tanks. I think I've mentioned it in other posts to you, but I would get rid of a few of the larger fish and see what happens with improved health in your tank. You have had issues with health lately and I think that the overstocking is the likely cause.
Fish with HLLE that are put into environments with less stress, proper diet and pristine water quality can bounce back.
I have had a blue tang that got it. This was back in the day, pre-Internet and my LFSs did the "your tang will be fine in a 75g reef". Moved it into a 300g (girlfriend's tank at the time) and it looked good as new several months later. She took in a black tang from a LFS (they gave it to her for $30, prior to us dating) and it bounced back...only had a couple little spots. I've had a couple friends with a yellow and a purple that got it. Same thing...both in small tanks, both moved to larger, both bounced back. Ive observed stories online from people that had fish with HLLE and "cured" it. I've been doing this for years, so I could go on and on with stories.
I'm telling ya, IMO, stress, water conditions and diet are at the root of most fish ailments. You rarely see a properly stocked tank that is maintained properly that has major issues. There may be rare instances where a tank is beating the odds for a while, but that is more luck, IMO.