Could my old rock be causing my issues?

[subsea]

At less than 1", the substrate would not require vacuuming. Keep it clean with aggressive circulation and janitors.

If you are increasing your algae filtration, then the simultaneous use of protein skimmer will remove nutrients at the decrease of ATS capacity. Why go to the expense of installing ATS and then limit its use.

As you say, you wish to feed heavy. It is up to you to balance nutrients in and out.

[Wade]

Just a thought on the ATS. Not sure about executing it yet.

@victoly: I think all I'm going to do at this point is vacuum out about half of my substrate and reduce it down to less than an inch as Patrick suggests and then try to keep it circulated and healthy. No other changes until I see how that pans out.

[Wade]

I started the process of reducing the sand bed down to an inch or less. **** nasty it was. Amazing how much detritus poofed out of it and covered just about everything. I had to go back with a turkey baster and blow off the coral. I've got some more to remove this week and then I should be all set. I'm going to leave what's under the rocks for now. I'm thinking that may slowly get pushed out as I stir up the sand around the edges. I've got a star fish living under each column and a convict blenny that has caverns dug out under each and he travels between the two daily. I may have to remove that sand in the future, but I think I'll hold off for now. My Florida fighting conk isn't going to like it a bit. Do they have to have a deep sand bed to survive? If so, I may have to find another home for it.