Running gfo but phos keep rising

bglegs · 07/02/2011, 08:48 AM

I started running gfo reactor.First before before using I got a reading of .12 (hanna ).I ran for reactor for 48hrs and checked level .03 so I thought I was on the right path so I changed out again and checked the reading was higher.I have been changing out gfo every 48hrs for two weeks.My recent reading was .23.I"m wondering if the hanna meter is off.Although I checked ro water and that reads .00. I recently replaced all my ro/di filters including two membranes.I don't have an algae problem so I'm really confused.Could the live rock be leaching phos.Any advice will be appreciated..

fishchef · 07/02/2011, 09:01 AM

I have a Checker also and recently I used the other vial it came with. Wow, what a crazy high reading! So then I did a second test with the other vial. Now I got a .02 instead of .65.The lower reading was more in line with the LFS. My results have always compared with my friends Lab Hanna at his LFS. He told me to use the vial that mostly compares in results to his unit. Now my tests are more consistent. I've had my Checker for almost 2 years and I knew the cleanliness of the vials was critical. The shape of the glass also effects readings. Probably why you get two.

ColaAddict · 07/02/2011, 09:40 AM

Phosphate testers are known for being very unreliable. The best thing you can do is a visual check of your aquarium, if there is no algae growing, then you are good. If you have SPS and they are showing growth, then you are also good.

fishchef · 07/02/2011, 10:07 AM

Visual is tough. I need some kind of guide. Switching out GFO too often can be expensive and bad for your corals. Yes, PO4 can be absorbed into your LR if you haven't been using it and then released back into your system. My local water Guru says no more than evey 3 weeks. It took me over a year to get my PO4 down to below .55 changing the GFO every 3-4 weeks. I didn't have algae either, just that pesty cyno. The aftermath of using a poorly designed test kit. Phosphate is a building block of coral growth and stripping it out to quickly can damage health.

07/02/2011, 08:48 AM	#1
bglegs Registered Member Join Date: Dec 2007 Location: Illinois Posts: 267	Running gfo but phos keep rising I started running gfo reactor.First before before using I got a reading of .12 (hanna ).I ran for reactor for 48hrs and checked level .03 so I thought I was on the right path so I changed out again and checked the reading was higher.I have been changing out gfo every 48hrs for two weeks.My recent reading was .23.I"m wondering if the hanna meter is off.Although I checked ro water and that reads .00. I recently replaced all my ro/di filters including two membranes.I don't have an algae problem so I'm really confused.Could the live rock be leaching phos.Any advice will be appreciated..

07/02/2011, 10:07 AM	#4
fishchef Registered Member Join Date: Feb 2009 Location: St. Louis, MO Posts: 1,222	Visual is tough. I need some kind of guide. Switching out GFO too often can be expensive and bad for your corals. Yes, PO4 can be absorbed into your LR if you haven't been using it and then released back into your system. My local water Guru says no more than evey 3 weeks. It took me over a year to get my PO4 down to below .55 changing the GFO every 3-4 weeks. I didn't have algae either, just that pesty cyno. The aftermath of using a poorly designed test kit. Phosphate is a building block of coral growth and stripping it out to quickly can damage health. Last edited by fishchef; 07/02/2011 at 10:19 AM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
if running gfo and sulfur denitrator, would you run a fuge?	noobtothereef	The Reef Chemistry Forum	2	10/01/2010 06:50 PM
see a lot of folks with algae issues, run GFO/Phos remover?	geaux xman	New to the Hobby	2	09/28/2010 10:16 PM
running carbon in phos reactor	Jonnyacrofeed	Reef Discussion	12	07/03/2007 10:42 AM
Does anyone run GFO without a Phosphate (e.g. Phosban or Fluidised) Reactor?	dirtyreefer	SPS Keepers	4	10/13/2006 09:57 AM
Best way to run GFO (phospate remover)?	Dag	Lighting, Filtration & Other Equipment	4	08/16/2006 01:08 PM

07/02/2011, 09:01 AM	#2
fishchef Registered Member Join Date: Feb 2009 Location: St. Louis, MO Posts: 1,222	I have a Checker also and recently I used the other vial it came with. Wow, what a crazy high reading! So then I did a second test with the other vial. Now I got a .02 instead of .65.The lower reading was more in line with the LFS. My results have always compared with my friends Lab Hanna at his LFS. He told me to use the vial that mostly compares in results to his unit. Now my tests are more consistent. I've had my Checker for almost 2 years and I knew the cleanliness of the vials was critical. The shape of the glass also effects readings. Probably why you get two.

07/02/2011, 09:40 AM	#3
ColaAddict Moved On Join Date: Apr 2011 Location: Northbrook Posts: 370	Phosphate testers are known for being very unreliable. The best thing you can do is a visual check of your aquarium, if there is no algae growing, then you are good. If you have SPS and they are showing growth, then you are also good.