While HMF are considered great filters, the reason I am thinking of moving back to the 3 AC110s is the simple reason when my rhom died I was running the 3 AC110s and kept the last aimara for 7+ months without any of these health issues. Within ~2-3 days of installing the HMF is when he jumped out of the tank, and since then I had issues with the GATF that died, and now issues with this guy. I can't say the HMF is the problem but I am just think it might make things simpler and the AC110s at least will be more resilient than the HMF.