RowaPhos Dosing

Hey everyone, I’ve been fighting high phosphates for about 2 months and they have steadily been coming down. I was at .7 back in July and I’m now at .11. I have been using Chemipure blue but picked up RowaPhos the other day at the LFS. My question is: I want to lower phosphates from .11 to .015. RowaPhos says 1 gram per gallon in my 45 gallon tank. My concern is that the RowaPhos says it will lower 3ppm at standard dose. Is half a dose still too much and will risk bottoming out my phosphates? Thank you ahead of time

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@BackbayReef
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Joined May 2026265 posts1,033 pts★5.0(2)
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Sep 6#2

Share your experience…

I haven’t dosed RowaPhos in years but the rule of thumb for me has been to only lower by a maximum of 0.03ppm per 24hrs. You can push it to 0.05ppm if you don’t have sensitive fish / corals. Bottom line: slow & steady win the race. Good luck!

— /yolo

@janiners305

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Joined Aug 202672 posts284 pts📍 Glendora, CA

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Sep 7#3

@BackbayReef wrote: I haven’t dosed RowaPhos in years but the rule of thumb for me has been to only lower by a maximum of 0.03ppm per 24hrs. You can push it to 0.05ppm if you don’t have sensitive fish / corals. Bottom line: slow & steady win the race. Good luck!

Definitely agree with this 100%. In my experience, Rowa (while great stuff) can bottom the phosphates out incredibly quickly. Learned that on our 135gal we had. Our rocks were so saturated with phosphates that they just kept leaching out. We tried everything we could think of, but the only thing that worked to help bring them down was Rowa. We only ever ran it at a half dose, if I remember correctly, though. We had a full SPS tank and did bottom them out completely once.

— 105 gallon mixed reef - SPS/Torch/Goni

@BackbayReef

SCRM😎 Cool Kids🧠Reef Guru

Joined May 2026265 posts1,033 pts★5.0(2)

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Sep 7#4

@janiners305 wrote: Definitely agree with this 100%. In my experience, Rowa (while great stuff) can bottom the phosphates out incredibly quickly. Learned that on our 135gal we had. Our rocks were so saturated with phosphates that they just kept leaching out. We tried everything we could think of, but the only thing that worked to help bring them down was Rowa. We only ever ran it at a half dose, if I remember correctly, though. We had a full SPS tank and did bottom them out completely once.

You know what will drop PO4 faster, within 24hrs? Lanthanum Chloride-based solutions will definitely do the trick. I’m dosing 10mL a day into a fleece roller to keep PO4 at bay. People reported having issues with tangs but I’ve been super lucky.

— /yolo

@janiners305

SCRM😎 Cool Kids🌸Polyp Whisperer

Joined Aug 202672 posts284 pts📍 Glendora, CA

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Sep 7#5

@BackbayReef wrote: You know what will drop PO4 faster, within 24hrs? Lanthanum Chloride-based solutions will definitely do the trick. I’m dosing 10mL a day into a fleece roller to keep PO4 at bay. People reported having issues with tangs but I’ve been super lucky.

Good to know! LC wasn't something I personally knew about back in 2016-2018...I have heard good things about it this time around, but just haven't had an issue with the higher phosphates.

— 105 gallon mixed reef - SPS/Torch/Goni

RowaPhos Dosing

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