Phosphate not dropping after adding Phosguard?

[rennjidk]

I suspect that it is still leeching back out from the rocks and substrate, but I didn't think it would be this substantial in a 14g system volume tank. Tank sat for a year without testing, feeding TDO pellets to my clowns and a pair of BTAs.

14g water volume, hanna ulr po4
1/31 9.5g and 3g WC
2/1 8g WC, ICP sample taken immediately after, 0.02ppm results
2/6 first test 0.45ppm
2/7 1/3c Phosguard added to reactor, 8g WC, 0.20ppm, 2g WC
2/8 0.19ppm

I don't understand the 0.01ppm drop after 24hrs of Phosguard. That's within the margin of error. Have I really bound up that much Po4 in the system?

 

[vetteguy53081]

I suspect that it is still leeching back out from the rocks and substrate, but I didn't think it would be this substantial in a 14g system volume tank. Tank sat for a year without testing, feeding TDO pellets to my clowns and a pair of BTAs.

14g water volume, hanna ulr po4
1/31 9.5g and 3g WC
2/1 8g WC, ICP sample taken immediately after, 0.02ppm results
2/6 first test 0.45ppm
2/7 1/3c Phosguard added to reactor, 8g WC, 0.20ppm, 2g WC
2/8 0.19ppm

I don't understand the 0.01ppm drop after 24hrs of Phosguard. That's within the margin of error. Have I really bound up that much Po4 in the system?

phosguard often an alternative and not a solution and if it works, takes a few days to start working. Best and effective methods are:
2-4 gallon water changes daily for 10-14 days
Reduce amount fed
assure skimmer running efficiently or add one if none
Do not use tap water if you are
ASSURE YOURE NOT GETTING FALSE READINGS

 

[VintageReefer]

Doesn’t matter how big or how small the tank is. Rock can take weeks or months for all the phosphate to unbind. For this to happen, phosphate in the water column needs to substantially drop, and stay low, so it can unbind from rock and create new equilibrium.

 

[CrayHawk]

Are there any visual cues for the rock unbinding? I have high phosphates. Have an ATS now and phosphates are still high but now I have air bubbles on my live rock.

 

[Jessereef]

I suspect that it is still leeching back out from the rocks and substrate, but I didn't think it would be this substantial in a 14g system volume tank. Tank sat for a year without testing, feeding TDO pellets to my clowns and a pair of BTAs.

14g water volume, hanna ulr po4
1/31 9.5g and 3g WC
2/1 8g WC, ICP sample taken immediately after, 0.02ppm results
2/6 first test 0.45ppm
2/7 1/3c Phosguard added to reactor, 8g WC, 0.20ppm, 2g WC
2/8 0.19ppm

I don't understand the 0.01ppm drop after 24hrs of Phosguard. That's within the margin of error. Have I really bound up that much Po4 in the system?

It takes time to work

 

[rennjidk]

phosguard often an alternative and not a solution and if it works, takes a few days to start working. Best and effective methods are:
2-4 gallon water changes daily for 10-14 days
Reduce amount fed
assure skimmer running efficiently or add one if none
Do not use tap water if you are
ASSURE YOURE NOT GETTING FALSE READINGS

Readings seem to track, No3 for example is where it should be with the large volume of WCs and subsequent dosing of NaNO

It's my understanding that Phosguard, while not as effective as GFO, should act in the same way, though around 70% binding capacity.

 

[rennjidk]

Are there any visual cues for the rock unbinding? I have high phosphates. Have an ATS now and phosphates are still high but now I have air bubbles on my live rock.

I don't see anything out of the ordinary, other than an immediate drop with WC, and then return to previous levels within a day.

 

[rennjidk]

Doesn’t matter how big or how small the tank is. Rock can take weeks or months for all the phosphate to unbind. For this to happen, phosphate in the water column needs to substantially drop, and stay low, so it can unbind from rock and create new equilibrium.

That seems to be my issue and what I don't quite understand. WCs have an immediate impact (confirmed with ICP), but running roughly 4x the recommended Phosguard in a reactor doesn't seem to bring the water levels down. I speculated that I might be exhausting the media fairly quickly, but I'm sitting at a 0.19ppm equilibrium. I should be seeing some sort of reduction at that level, at least I think?

 

[VintageReefer]

It’s possibly slowly getting removed by phosguard media but at same time slowly getting back filled with phosphate from rock. Eventually, the numbers will lower but the media needs to be replaced very often

When I used a phosphate reactor I hit the same issue. My media would last 2-4 days and need to be replaced. My numbers never really went down either

I got an algae turf scrubber. It works 18 hours a day absorbing phosphates, doesn’t need media, is silent, and natural. And basically free to run. Just power the leds and mine also needs an air pump.

Now my phosphate has been .02-.05 for the past 30 months with no water changes

 

[rennjidk]

As a follow up, should I be worried about driving silicates down to undetectable levels with frequent media changes, if Phosguard really binds silicon as they claim? This is now a full acro tank, frags went in today.

 

[VintageReefer]

I have limited knowledge with silicates. I never had to test for them or worry about them. Maybe someone else can chime in

 

[dyno]

Secret weapon. Phosphate-e only dose into a 5micron sock!

 

[Randy Holmes-Farley Verified Community Expert]

Are there any visual cues for the rock unbinding? I have high phosphates. Have an ATS now and phosphates are still high but now I have air bubbles on my live rock.

No, that is not related to phosphate being removed from the rock.

 

[Randy Holmes-Farley Verified Community Expert]

I suspect that it is still leeching back out from the rocks and substrate, but I didn't think it would be this substantial in a 14g system volume tank. Tank sat for a year without testing, feeding TDO pellets to my clowns and a pair of BTAs.

14g water volume, hanna ulr po4
1/31 9.5g and 3g WC
2/1 8g WC, ICP sample taken immediately after, 0.02ppm results
2/6 first test 0.45ppm
2/7 1/3c Phosguard added to reactor, 8g WC, 0.20ppm, 2g WC
2/8 0.19ppm

I don't understand the 0.01ppm drop after 24hrs of Phosguard. That's within the margin of error. Have I really bound up that much Po4 in the system?

Phosguard in a reactor with good flow for 24 h and phosphate steady at 0.2 ppm is likely depleted, and I'd replace it.

We are talking about a small amount that is not very expensive.

 

[Randy Holmes-Farley Verified Community Expert]

As a follow up, should I be worried about driving silicates down to undetectable levels with frequent media changes, if Phosguard really binds silicon as they claim? This is now a full acro tank, frags went in today.

Silicate is only primarily used by sponges and diatoms in out aquaria. I do like to dose it to promote both of those, but it is irrelevant for corals.

 

[Mr. Mojo Rising]

It took me 2 years to suck out the phosphate. For 2 years it would rise to .45. I would put 2x, 3x, 4x the amount of rowaphos which would drop the phosphate to .1, then within 1-2 weeks it would climb back to .4.

I was changing rowaphos every 1 or 2 weeks. I spent an incredible amount of money on rowaphos in those 2 years

I would say that phosguard is good for minor cases, but in my case (and I suspect in yours as well), rowaphos is a better option.

I still have a full container of rowaphos, I can send it to you collect (from Canada)

 

[jda]

Some chemist told me long ago that Fe2o3 and Al2o3 have the same binding sites, so both should be plenty effectice to remove large amounts of po4... like pretty much identical with similar surface area.

The rock and sand can bind a tremendous amount of po4. I added over 50 ppm of po4 to a 10 gallon tank with just a phosban reactor about half full of calcium reactor media, and the end phosphate in the tank was 0.16. This means that at most, all that you are are going to be able to remove at a time is .16 and maybe a bit more that unbinds during the period that the reactor is on the tank. The point is that it can take a lot of changes and time to fully remove the po4.

This is why I am always miffed a bit that people add po4 to their tanks when most of it ends up in the rock and sand. Most of them have plenty of po4 too, they just want it higher since somebody on the internet sold them "to feed their corals."

 

[ReeferA]

Nothing removes phosphate than Phosphate-E by Brighywell. I use it along with Neo-Phosphate to raise it when it's zero. I had used Topic marin also but Brightwell works faster and it's cheaper.

​

 

[Randy Holmes-Farley Verified Community Expert]

Nothing removes phosphate than Phosphate-E by Brighywell. I use it along with Neo-Phosphate to raise it when it's zero. I had used Topic marin also but Brightwell works faster and it's cheaper.

​

What? You dose P and bind it with lanthanum at the same time?

 

[rennjidk]

Phosguard in a reactor with good flow for 24 h and phosphate steady at 0.2 ppm is likely depleted, and I'd replace it.

We are talking about a small amount that is not very expensive.

I'd like to follow up again, in regards to Phosguard specifically, if you don't mind.

I came across a reef central link from 2007 which referenced a study you published, linking Phosguard specifically to leeching Al. I've also found a few more recent quotes like this one on R2R

While I am not a huge fan of phosguard due to the possibility of aluminum release, there is absolutely no possibility that it reduced salinity, and if there are any alkalinity effects, they are minor and short term. If you got a bigger alk drop, it was for other reasons.

I have seen a few indirect mentions citing your study, stating that as long as it is rinsed thoroughly and not tumbled, the risk of Al leeching is miniscule, due to the concentrations in your origin experiment. I was just wondering if you cared to elaborate, or if your opinion has changed over the past couple years. (I'm in no way challenging your findings or the original study, I'm just curious of your current day thoughts)

Furthermore, there's a strong exothermic reaction when it is rinsed with water, as well as, quite a bit of off gassing. Can you explain what exactly is getting released? It's not every day us non-chemistry folks add water to something and get met with a face full of smoke/vapor.

Thanks in advance!