ROWAPHOS amounts

Panky · Jul 14, 2018

Hitman said:
What’s the difference if you have black or white sand @Randy Holmes-Farley ? I have a mix of black and white crushed coral for substrate and looking into getting rowaphos as high cap GFO just isn’t cutting it for my tank. I can’t seem to keep PO4 below 0.10 ppm to save my life.

Hell my po4 is at 1.93. Will rowa work? How much do I need to use. 610 Gallon DT & Sump combined minus 300 pounds of live rock and sand

Randy Holmes-Farley · Jul 14, 2018

Panky said:
Hell my po4 is at 1.93. Will rowa work? How much do I need to use. 610 Gallon DT & Sump combined minus 300 pounds of live rock and sand

GFO will always work to bind phosphate if you use enough and change it often enough, but it will take a lot for that high of a starting point. It's not possible to say how much since there's probably more bound to the rock and sand then in the water, and it will come off as the level drops. Water changes are not a good approach for that reason.

Randy Holmes-Farley · Jul 14, 2018

Hitman said:
What’s the difference if you have black or white sand @Randy Holmes-Farley ? I have a mix of black and white crushed coral for substrate and looking into getting rowaphos as high cap GFO just isn’t cutting it for my tank. I can’t seem to keep PO4 below 0.10 ppm to save my life.

Aragonite sand will bind substantial phosphate, and it may take substantial treatment to remove it all. Not sure on black sand, and black sand may also leach metals.

What is the current phosphate value? It may not be worth agonizing over.

Hitman · Jul 14, 2018

Randy Holmes-Farley said:
Aragonite sand will bind substantial phosphate, and it may take substantial treatment to remove it all. Not sure on black sand, and black sand may also leach metals.

What is the current phosphate value? It may not be worth agonizing over.

.38 PO4 and after 100 gallon weekly water changes and running BRS high cap GFO there no change. This system has been up and running for 18 months with no issues till mid April when out of nowhere I had a GHA and Byrop out break which got me to buy both a Salifert and the Hanna Ultra Low Phosphate checker and they are reading almost the same.

Randy Holmes-Farley · Jul 15, 2018

Hitman said:
.38 PO4 and after 100 gallon weekly water changes and running BRS high cap GFO there no change. This system has been up and running for 18 months with no issues till mid April when out of nowhere I had a GHA and Byrop out break which got me to buy both a Salifert and the Hanna Ultra Low Phosphate checker and they are reading almost the same.

It may take a lot. One member showed that 1 pound of rock in 5 gallons of water could hold (and potentially release) 50+ ppm of phosphate when there is only 0.16 ppm in the water itself.

https://www.reef2reef.com/threads/phosphate-absorption-rates-in-aragonite.352405/page-4#post-4501532
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