I like you have had coral issues over the past couple years... Currently I run a skimmer, cheato, LR and LR rubble in the refuge/sump area. NO CARBON!!! 
 
I do my weekly water changes, and watch my parameters, and can say things are easier and seem to be improving. 
 
I use to do Zeo, pellets, and every other thing. I keep it simple and am now using Prodibio, with some nice results from it. Corals are actually starting to color up, brown is dissappearing. 
 
So I do recommend the simple method. Just my 2 cents from someone who has wasted alot of money in this hobby. 
		
	
		
		
		
		
			
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Setup: 180G DT, 105G Refuge (approx. 300lbs LR, 150lbs Aragonite) 
Hardware: Super Reef Octopus SSS-3000, Tunze ATO, Mag 18 return, 2x MP40W, 2X Koralia 4's Wavemaker 
Lighting: 5ft Hamilton Belize Sun (2x250W MH, 2X80W T5HO) 
Type of Aquarium: mixed reef (SPS & LPS) with fish 
Dosing: Mg, Ca, Alk 
			 
		
		
		
		
	
		
		
	
	
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