i have the same mine a 4 foot
i am getting an emerald crab and another clean up crew soon though apparently crabs help alot 


I've been battling this myself ever since my move.
I've made some progress, but cleaning is just not feasible. I've cleaned the rocks I can get to, but the huge base rocks and large rocks with coral attached I have no viable way to remove from the tank and clean.
I've got a decent clean up crew, and I have phosphate absorber, macro algae in a fuge, and weekly water changes. Seems to be helping, but it's slow going.