[DiverDude]

I too am having an HA problem. Ironically, it's come back SINCE I started running pellets.

I do a 15% water change every 7 days (max)
I feed very little
My Bioload is low
Pellets tumble hard

I've reduced my photo period and added a chiller and things are a bit better but not great.

I rented a sea hare from Red Coral but they only had a small one. I thougt it might be good to get in tight areas but the thing spent 2 days on the glass then disppeared into the rockwork never to be seen again. I tore half the tank apart to find him and nothing. Now I'm doing even more water changes !!

There is no easy answer/solution !