Pros and cons on running GFO?

Twisted_Blenny · Dec 2, 2017

ive been reading a lot that people love to run GFO or hate it. Can anyone explain their experience with it? thank you!

lauderdalestunner · Dec 2, 2017

Works well for me. IMO you can have high nitrates with low phosphate and hardly have any algae growth.

XNavyDiver · Dec 2, 2017

My experience: I run it in a brs reactor. I started off with just about a cup of it. I measured my po4 everyday when I first started. Once my po4 started to level off, I made adjustments from there. First adjustment was to open the small inlet valve on the reactor a bit more for a little more flow. When the po4 level failed to creep down further, I just added a little bit more gfo to the reactor, then continued to measure on a daily basis. Once my level of measured po4 (using the Hanna ULR) was where I wanted it to be, in the .03 to .06 range, I just kept everything the same. I will take a po4 reading about every 3 or 4 days to check how everything is going. Once readings start to creep back up, I just replace the exact amount of gfo.

Ocelaris · Dec 2, 2017

I used to use gfo, but for the past 6 months I've been unable to keep phosphates up so I feed like crazy and test with the Hanna ulr phosphorus tester, and it still barely is acceptable. I've found phosphates to be the coral limiting nutrient for my tank. I have nitrates galore, but if my phosphates drop below 0.04 everyone starts looking pale and if it stays below for long enough I get bleaching.

Cory · Dec 3, 2017

I had 0ppm po4 via Hanna. Still had some algae growth. Added iron oxide algae grew more and my coral bleached or lightened. It's good for some but not all tanks. Imo herbivores and lots of coral covering the rock is the best way to prevent algae growth. Corals need .10ppm or less but not less than .01ppm po4.

Salty1962 · Dec 4, 2017

PRO-
Helps keep your phosphates down when dialed in correctly keeping algae growth down.
CONS-
If not used correctly, it can strip your tank of nutrient too quick causing loss of corals. You need to test frequently and go very slow when starting it up. I use 1/2 of the recommended amount. You shouldn't need to run for extended periods unless you feed heavy and have excess nutrients.