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			#1  
			
			
			
			
			
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|  Gfo question I am new to running gfo My question is. Is there a way to tell if gfo is spent. My po4 was off the chart. To which I attribute my family feeding the tank twice a day. I was in aware of this so I fed in evening. I have remedied the feeding schedule and done wc. I know most People change gfo once a month or when they see a rise in po4 | 
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			#2  
			
			
			
			
			
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|   Test the outlet of your gfo reactor. If it's anything but 0ppm then change it. | 
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			#3  
			
			
			
			
			
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|   Will do.  Wasn't sure if the outlet would be zero or if it was a gradual procedure | 
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			#4  
			
			
			
			
			
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|   Thats what i was thinking as well, Im not sure the water coming out of the reactor would be filtered to zero in a single pass. Ive heard every 6 months approx or when Phos starts to rise. I dont think there is any other way to tell as far as I know. 
				__________________  - 33 Gal - 20Gal Sump, MP10/Hydor Powerheads, Aquaticlife 4x T-5HO, Vertex IN100, TLF w/Biopellets, Tunze ATO -45GAL Build in Progress!- | 
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			#5  
			
			
			
			
			
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|   Sorry my fingers were typing but my brain was asleep lol.  In most cases, no you will not have 0 phos on the outlet. So a better indication would be when the outlet is at the same phosphate level as the overall po4 level of the system. | 
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			#6  
			
			
			
			
			
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|   I change mine every 4-5 weeks 
				__________________ 250G DD LED SPS R.I.P. 180G LED SPS 80"x36". 300G custom build Owner of Mountain Ridge Heating and Gas Class A gas fitter, HVAC | 
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			#7  
			
			
			
			
			
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|   If you have high phosphates gfo can be exhausted in a very short time (days) so if your battling problems it might be a good idea to test ( from the output of the reactor) frequently to stay on top of the problem. | 
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			#8  
			
			
			
			
			
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|   +1 to the above, and I'll add the same ... Test your output, compare it to your system, and change your media every 4-6 weeks if all is good. Keep a record of what's happening so you can keep an eye on when you initially need to change it and go from there. | 
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			#9  
			
			
			
			
			
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|   Thanks everyone.  I tested outlet and It is the same as tank. I'll change it today |