Changing GFO

[Shilpan]

Hey guys changed my GFO recently. I use Seachem phosnet in a Seachem bag with low flow as reccomemded. I have macroalgae and feed 1/2 cube a day and 1/3 algae sheet 3x a week.

So my phosphate test always reads 0 (tried multiple test kits), however finally I've had cyano come back. Changed it and cyano went away. Phosphates still at 0.

The GFO last 6 months and 3 weeks. That's amazing and far more than I expected. You guys have any similar experiences? Does anyone else also need to rely on things other than phosphate levels to decide when to remove GFO?

 

[lmforbis]

The phosphates are there and being used up by the cyano and macro algae. Not unusual for them to read 0 but they really aren't. I just change GFO every 3-4 weeks. I never test for phosphate.

 

[Shilpan]

Cost for that?

 

[2quills]

Kinda the same here. Just change it about every month or so. The big container of high capacity gfo from BRS has lasted me a little over 2 years now. So a little less than $5 a month roughly.