Angry Phosphate Man: Mitigating High Phosphates In Your Reef Aquarium

How concerned are you about high phosphates in your tank?

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    Votes: 125 21.4%
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revhtree

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Today let's talk about.......Mitigating High Phosphates In Your Reef Aquarium...dum dum dum!

Phosphate-Figure-1.gif

Angry Phosphate Man

The first thing we need to get out of the way is that fact that phosphates is not something that can be avoided. It can't be avoided but it can certainly be minimized. Why is that important? Well if you like uncontrollable algae then you need not worry about your level of tank phosphates. BUT if you're like most reef aquarium hobbyists then you want a clear, beautiful and nuisance algae free tank! So if phosphates can't be avoided then how do you mitigate it in your aquarium? Let's talk about it!

1. What can you do to keep phosphates under control and at levels that you are comfortable with? What are some things YOU do?

2. What is a comfortable level of phosphates for you in your aquarium?



image via @ReefNerd
dB8NouU.jpg
 

lapin

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Mine are at .147 Hanna UL checker
Mixed reef of mostly soft ( nems, shrooms leathers and LPS corals)
I do run GFO
My NPS tank is plumbed to my main tank. It gets fed a lot of small foods Oysterfeast , R.O.E, Phytofeast, Rotifers ect...
 

jda

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I use a fuge, skim heavy and change water from time to time. This keeps me about 1-3 parts per billion on Hannah Ultra Low - I do not like to get over 10 ppb. I will use some Lanthanum Chloride to treat new-to-me used rocks that have been mistreated - easy and cheap.
 

SDK

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1. What can you do to keep phosphates under control and at levels that you are comfortable with? What are some things YOU do?

I run a good skimmer/refugium combo that keeps my nitrates around 2 with no other intervention, but my phosphates slowly creep up over time. I keep a small amount of GFO in my secondary filter sock slot and do a small quarterly dose of LaCl when it starts drifting up close to .1 ppm

2. What is a comfortable level of phosphates for you in your aquarium?

For me, anything between .02 and .08 ppm seems to be the sweet spot.
 

zoaprince

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I have mostly Zoas so I actually WANT higher phosphates. I'm at ~0.03 right now but would like it around ~0.1. Unfortunately it doesn't budge :/
 

stanleo

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I have a fuge with chaeto and run my skimmer continuously. I also am strict about 20 gallon water changes every two weeks. My phosphates have never been above 0.1 on Salifert and usually stay at 0.03. I test weekly and if it ever goes above a 0.25 I might start looking at other methods but for now this is all I have to do.
 

Timfish

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I use GFO and water changes to help control phosphates. I haven't seen a correlation between PO4 and algae so seeing levels above 0.1 or 0.2 mg/l doesn't bother me. (I've seen PO4 levels increase asa nusance algae dissapears when people have asked my to fix algae problems in their systems.) Higher levels aren't too concerning but are reason to start reducing it.

Unfortunately we can't test for all the forms of phosphorus in our systems so there is no magic number for PO4/DIP except keeping it above the .03 threshold level identified by Southampton University. This paper by Christine Ferrior-Paģes, et al, is a good review of phosphorus in marine animals with simbionts. Besides Dissolved Inorganic Phosphorus aka PO4 (DIP) there's also Dissolved Organic Phosphorus (DOP) and Particulate Organic Phosphorus (POP) taht's being used by corals. (So far there doesn't there's no evidence corals are using Particulate Inorganic Phosphorus or PIP.) Here's fig 4 from their paper:

DIP DOP POP.jpg


Here's some other papers for those interested:

An Experimental Mesocosm for Longterm Studies of Reef Corals

Phosphate Deficiency:
Nutrient enrichment can increase the susceptibility of reef corals to bleaching:

Ultrastructural Biomarkers in Symbiotic Algae Reflect the Availability of Dissolved Inorganic Nutrients and Particulate Food to the Reef Coral Holobiont:

Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates

Effects of phosphate on growth and skeletal density in the scleractinian coral Acropora muricata: A controlled experimental approach

High phosphate uptake requirements of the scleractinian coral Stylophora pistillata

Phosphorus metabolism of reef organisms with algal symbionts
 
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revhtree

revhtree

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Thank you all for the great info so far!
 

Jax15

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Chaeto fuge and Nyos skimming have been highly effective. I prefer to run between 0.03 - 0.05. I don't have much success with zoas, probably because this number is low, but my SPS seem to like it.

What I also like about the fuge is you can just scale your coral feeding along with the growth. After harvesting chaeto, I feed reef roids a bit less. As it grows, I up the feeding. That way the export is usual in balance.
 

ZodFather

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I run GFO in a media reactor. That, along with regular water changes generally keep my phosphates in my comfort zone, which is generally 0.04-0.11. I know it's time to change out my GFO when they start creeping up into the 0.15-0.20 range.
 

Marc2952

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I wish i had problems with high phosphates, seems to be easier then dealing with phosphates dropping to 0 everyday lol my phosphates drop from 0.08 to 0.00 every 24 hohrs and theres not a single spec of algae in my tank. I try to keep mines at .15 since it gives me time to catch it before ot drops too much.
 
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Do you have a frag tank, frag rack or some other place for coral frags currently?

  • YES (tell us in the thread)

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